1. Introduction:
Many critical scholars have noticed the fourth gospel has signs of insertions, additions and reshuffling, suggesting its writing followed a long process:
"It is today freely accepted that the fourth Gospel underwent a complex development before it reached its final form." Introduction to the Gospel of John, The New Jerusalem Bible
Furthermore, it is more and more accepted its author knew about the synoptic gospels (and NOT a gospel of signs & a passion narrative, none evidenced to have existed).
In agreement with these later observations, I will proceed to flag out the "smoking guns" and propose the solutions.
Everything will fit and be easily explained. And if it fits, don't dismiss!
This work is thoroughly documented, accounting for any insertion, addition and relocation. For details, my readers can go to the subsequent pages, designed for easy navigation throughout.
Next is a preview of some of the conclusions.

2. Synopsis:

2.1 The first (original) gospel:
It was written around 75-80C.E. when Mark's gospel (GMark) was known in the community. This gospel was very COHERENT, with the material drawn from GMark considerably embellished. There are many clues pointing to the fact the author knew about GMark but was not aware of the other synoptic gospels (as explained later in my comments within the text of the original version).
Here, most of Jesus' summer activities in Galilee are not narrated, but time is allocated for them:
Jn2:12 "After this He went down to Capernaum, He ... and His disciples; and they did not stay there many days." (relating to Mk1:21-38)
Then from
Jn6:1 "After these things Jesus went away ... Then a great multitude followed Him,
[as explained from Mk1:37b "... "everyone is looking for you""]"
to
Jn7:1 "After these things Jesus walked in Galilee [from March/April (Passover) to October] ..." (relating to Mk1:39-9:50)
Afterwards, according to the original GJohn, Jesus goes to Jerusalem, Judea (7:2-10, 5:2-45, 7:11-10:39, October to December, from the feast of Tabernacles to the one of Dedication) and then across the Jordan (10:40-42, December to March/April), paralleling what "Mark" claimed (in a few words):
Mk10:1 "Jesus then left that place [Capernaum, Galilee] and went into the region of Judea and across the Jordan."
From there, as in GMark, Jesus goes to Jerusalem for Passover and his crucifixion.

Note: essentially, regarding Jesus' public life, the original John's gospel relates major miracles in Galilee, but most of its content is dedicated to the alleged sojourn in Jerusalem during the fall. All main discourses (except the one in Capernaum (Jn6:26-59)) occur in Jerusalem.

The following sequence of events is the same for GMark and the original GJohn:
John_the_Baptist => In Galilee => Feeding_of_the_5000 => Walking_on_water => In Galilee => In Judea => Across_the_Jordan => Royal_welcome_into_Jerusalem => Disturbance_in_the_temple => Last_supper => Judas'_betrayal & Jesus'_arrest => Interrogation_by_the_high_priest and Peter's_three_denials => Trial_by_Pilate_&_crowd and Barabbas => Crucifixion_as_"King_of_the_Jews" => Burial => Post_Sabbath_empty_tomb

What is remarkable about the original version, made up of nine "blocks" of the final gospel (about 65% of it altogether), is that all the parts fit well with each other, requiring no additional wording to link them (but some, of the awkward kind, will be inserted for the later versions).
The gospel ended then at Jn20:10, after the 'empty tomb' segment (as in Mk16:8, the original end of GMark), when "... the disciples went away again to their own homes", as "prophesied" in Mk14:27-28 & Jn16:32 "... you will be scattered, each to his own home, and will leave Me alone"
One main addition (15:1-17:26) was made thereafter (Version 1x) within the body of the text. I do not consider it as part of the original version.

2.2 Alterations after GLuke was known:
Considerable additions and some relocations were done after Luke's gospel got known in the community. These changes were made in at least two phases.
All inclusions then can be related to passages in GLuke. The overall result was a rather disjointed gospel, with Jesus' ministry extended to at least two years (from one year and a few weeks), including more visits to Jerusalem (from two to four).
The end of the gospel was then pushed back to Jn20:23, in order to include a brief post-mortem appearance to the disciples, as the one in Lk24:36-49 right before the ascension (24:50-51).

2.3 Alterations after 'Acts' was known:
A few additions were made after 'Acts' appeared. Here, all inserted items have parallel notions occurring in 'Acts' (but NOT in GLuke).
The ending was again extended, this time up to Jn20:31, with a second post-mortem appearance to the disciples, one week later, as "allowed" by the "forty days" of 'Acts' (1:3) before the ascension (1:9).

2.4 Additions after the "beloved disciple" died:
Finally, the "epilogue" (Jn21:1-25ff), widely considered to be an appendix, was added on at the end. Furthermore, some notes, likely first written in the margin, were inserted in the body of the text, either at that time or earlier.
The gospel was finished then (97-105?).

There is little evidence to support the view the author(s) of the gospel used (or even knew about) GMatthew.
The "reinstatement" of Peter in the "epilogue" can be backed up by GJohn itself:
Peter becomes very prominent at the end of the gospel (Jn13:6-9,18:10). However, according to Jn13:24-25 & Jn20:3-8, Peter is second to another (unnamed) disciple who, as his latter contemporaries thought (Jn21:20-23), was being kept alive (because he was "the disciple whom Jesus loved"). But when this last known (alleged) eyewitness finally died (as Peter did long before), and obviously before the second coming, the main reason for his predominance was removed:
Jn21:22-23a "Jesus said to him [Peter], "If I will that he remain till I come, what is that to you? You follow Me." Then this saying went out among the brethren that this ["beloved"] disciple would not die. Yet Jesus did not say to him that he would not die ..."
The author of the "epilogue" may have decided then to "promote" Peter as the main apostle, according to GMark and GLuke (see also Lk22:32b).

3. The signs of change:

Note: later on this page, "proposed solution" will be upgraded to "conclusion" with additional pieces of evidence drawn from GLuke and 'Acts'.
Some of those "proposed solutions" or "conclusions" can be considered somewhat "abrupt", but they will make more sense in the following pages, into the very COHERENT results (such as the text of the reconstructed original GJohn). Be patient!

3.1 The delayed departure:
Jn14:31 "But that the world may know that I love the Father, and as the Father gave Me commandment, so I do. Arise, let us go from here."
Comment: what follows are some long monologues by Jesus (15:1-17:26) and no departure meanwhile!

Conclusion: 'The Last Supper (part 2)' was added on later.

3.2 The other side of the lake:
Jn6:1 "After these things Jesus went away to the other side of the Sea of Galilee (or Tiberias)."
Comment: prior to this verse, Jesus is in Jerusalem (5:1-47ff), some 70 miles away from the Sea of Galilee, a lake of about 10 by 6 miles. And when Jesus & disciples go back across the lake (6:17), they land in Capernaum!
Jerusalem cannot be considered a starting point to go across the lake, but Capernaum is (and the only named town on the lake visited by Jesus, in the whole gospel). And before going back there, the only time Jesus is at Capernaum occurs in Jn2:12.

Proposed solution: all the passages between Jn2:12 and Jn6:1 come either from latter additions or from relocations.

Note: the aforementioned passages (blocks) are:
a) 'Jesus cleanses the Temple and talks with Nicodemus' (2:13-3:21)
b) 'Jesus and John the Baptist', 'the Samaritan woman' and 'the nobleman's son' (3:22-4:54ff)
c) 'Jesus heals a sick at a pool in Jerusalem' (5:1-47ff)

3.3 Annas the high priest:
Jn18:13 "And they led Him away to Annas first, for he was the father-in-law of Caiaphas who was high priest that year."
Comment: Annas is not called a high priest here, but Caiaphas is. Furthermore, Jesus is brought to Annas first (and interrogated then) because of the later being the 'father-in-law'! This is rather unconvincing.
Jn18:24 "Then Annas sent Him bound to Caiaphas the high priest."

However, meanwhile, when Jesus is still in Annas' house:
Jn18:19 "The high priest then asked Jesus about His disciples and His doctrine."
Comment: now, but indirectly, Annas is also the high priest! But according to Josephus' Antiquities, there was only one high priest in office at any time; and during Jesus' public life, it was Caiaphas, not Annas, a former high priest.
Please note:
a) In GLuke, both Annas and Caiaphas are the high priests at the time (Lk3:2 "while Annas and Caiaphas were high priests").
b) Both "Luke" and "John" spelled "Annas" the same way, but Josephus' Antiquities, XVIII, II, 1, has "Ananus" (as the same high priest).
c) In GMark, Caiaphas is not named, but "the high priest" is written (14:53,61,63).
d) In GMatthew, "Caiaphas" is the high priest (26:57) and the only one mentioned.
e) GMark, GLuke & GMatthew do not have Jesus being shuttled from one high priest's house to another one.

Conclusion: Jn18:24 was added on and also the middle part (shown in Italics ) of Jn18:13. The original version had Caiaphas (correctly) as the only high priest. Then came GLuke ...

3.4 No reapparitions to the disciples (and Mary Magdalene) was anticipated by the author:

1) Let's consider:
Jn13:33 "Little children, I shall be with you a little while longer. You will seek Me; ..."
Jn13:36 "... "Lord, where are You going?" Jesus answered him, "Where I am going you cannot follow Me now, but you shall follow Me afterward."
Jn14:10 "... because I go to My Father and you see Me no more;"
Comment: there is no hint here Jesus will reappear to his disciples right after his resurrection. Actually, this is rather dispelled, more so in Jn14:10.

Note: However the following seems to go against the aforementioned point. But does it?
Jn14:18-20 "I will not leave you orphans;
[suggest a long-lasting action, not a mere short-lived apparition]
` I will come to you. A little while longer and the world will see Me no more, but you will see Me. Because I live, you will live also. At that day you will know that I am in My Father [in heaven], and you in Me, and I in you."
The above verses do not allude to a post-mortem apparition but refer to a spiritual "communion" between Jesus (in heaven with the Father) and the disciples on earth (as also in Jn14:28). How? The explanation is provided next:
Jn14:22-23a "Judas (not Iscariot) said to Him, "Lord, how is it that You will manifest Yourself to us, and not to the world?" Jesus answered and said to him, "If anyone loves Me, he will keep My word; ..."
Jn14:26 "But the Helper, ... whom the Father will send in My name, He will teach you all things, and bring to your remembrance all things that I said to you."

However, later in the text and in sharp contrast, in a short passage (16:16-23a), a reappearance to the disciples is prophesied:
Jn16:16 "A little while, and you will not see Me; and again a little while, and you will see Me, because I go to the Father."
Let's notice "you will see me" is presented as a consequence (and proof) of "I go to the Father". Of course this verse appears to be a later insertion, conflicting with the aforementioned quotes, more so:
Jn14:10 "... because I go to My Father and you see Me no more;"

2) Now, at the ending of the "empty tomb" passage, let's consider:
Jn20:10 "Then the disciples went away again to their own homes." (as implied in Mk14:27-28)
The above is "prophesied" as follows:
Jn16:32 "But a time is coming and has come, when you will be scattered, each one to his own home. You will leave all alone."
Comment: but then, some twelve hours later, why are the disciples together in Jerusalem (20:19), witnessing the resurrected Jesus?

Notes:
a) Let's notice "the disciples", and not (only) "Peter and the other disciple" (as in Jn20:2,3,4). In the preceding passage (Jn20:1-9), 'the disciples' does not appear. Consequently "the disciples" (going home) are not only the twosome who went to the tomb, but a much larger group.
b) It is said in the gospel some of the disciples do NOT have their homes in Judea:
Jn1:44 "Now Philip was from Bethsaida,..." (also Jn12:21)
Furthermore, through GMark (1:29), Peter & Andrew's home is in Capernaum.

3) Let's also consider:
Jn20:6-8 "then Simon Peter came, following him, and went into the tomb; and he saw the linen cloths lying there, and the handkerchief that had been around His head, not lying with the linen cloths, but folded together in a place by itself. Then the other disciple, who came to the tomb first, went in also; and he saw and believed."
Comment: this passage appears only in GJohn.

Note: the corresponding Lk24:12 is most likely a later interpolation because NOT in some ancient manuscripts and conflicting with 24:24 (in 24:12, only Peter goes to the tomb; in 24:24, several disciples went to the tomb).

4) Now, let's look at Mary Magdalene:
Jn20:11a "But Mary stood outside by the tomb weeping ... [after Peter and the other disciple went into the tomb]"
Comment: in Jn20:3-8, only Peter and "the other disciple" run to the tomb:
Jn20:3-4a "Peter therefore went out, and the other disciple, and were going to the tomb. So they both ran together ..."
There is no mention of Mary Magdalene (MaryM) running to the tomb with them (or even going back to it), which would enable her to allegedly see the resurrected Jesus, as in Jn20:14-17.

Proposed solution: there are many indications the original gospel did not include reappearances (as in the original GMark) and therefore ended with Jn20:10.

Note: in GMark (16:9-20), post-mortem apparitions (when Jesus says "when they [believers] drink deadly poison, it will not hurt them at all") and other oddities (some conflicting with Mk14:27-28,16:7-8) were added later on:
"the most reliable early manuscripts and other ancient witnesses do not have Mark 16:9-20" (The NIV Study Bible)
See here for more explanations.

3.5 'Thomas' and 'Thomas called the twin':
In three passages (out of four), Thomas (one of the twelve) is introduced as "called the twin" (or called didymus). They are:
a) 'Jesus resurrects Lazarus' (11:1-57)
b) 'Jesus reappears to Thomas and again to the other disciples' (20:24-31)
c) 'Jesus reappears to some disciples in Galilee' (21:1-25)
However, Thomas is presented as just 'Thomas' (13:5) in this (fourth) passage:
'Jesus teaches in Jerusalem and the Last Supper (part 1)' (12:20-14:31)

Proposed solution: how to explain this inconsistency? The three passages featuring "Thomas called the twin", an obvious embellishment, were added later, after 'Jesus teaches in Jerusalem and the Last Supper (part 1)' (with just plain 'Thomas') was written.

3.6 The non-narrated signs:

1) Let's consider:
Jn2:23 "Now when He was in Jerusalem at the Passover, during the feast, many believed in His name when they saw the signs which He did."
Jn3:2b "... for no one can do these signs that You do unless God is with him."
Comment: why, so early in Jesus' public life, have none of these (earlier) signs been narrated, when the first one (water into wine 2:1-11) has been and the next ones will be in details (as a trademark of GJohn), one by one?
Those next ones include:
- The healing of the nobleman's son in Galilee (4:43)
- The healing of the sick man at the pool of Bethesda, near Jerusalem (5:1-47)
- The healing of the blind man in Jerusalem (9:1-10:21)

The same non-narrated miraculous signs are mentioned later:
Jn4:43-45 "Now after the two days He departed from there and went to Galilee. For Jesus Himself testified that a prophet has no honor in his own country.
[why declare that, when next the Galileans welcome him, invalidating the previous statement? Except, of course, if the following is a later addition]
` So when He came to Galilee, the Galileans received Him, having seen all the things He did in Jerusalem at the feast; for they also had gone to the feast.
[confirmation that the unexplained alleged signs occurred in Jerusalem]"
Jn4:54 "This again is the second sign Jesus did when He had come out of Judea into Galilee.
[why bother to mention "the second sign" if Jesus already performed others in Jerusalem? The second part of the verse (in Italics) seems to have been added later: with the signs done in Jerusalem (relocated before 4:54), the previous statement had to be (awkwardly) "corrected"]"

Comment: if the (first) episode in Jerusalem (Jn2:14-3:21) was part of the visit when Jesus is crucified and does the "disturbance" (as in GMark), then the non-narrated signs (in Jerusalem) would have occurred after the (well "covered") 'sick cured' (5:1-9) and 'blind healed' (9:1-7). Latter additional signs performed in Jerusalem would not call for any narration.

2) Here, the aforementioned point becomes even more obvious:
Jn7:3 "His brothers therefore said to Him, "Depart from here and go into Judea, that Your disciples also may see the works that You are doing."
Comment: here is a confirmation Jesus did not go yet in Judea (Jerusalem) to perform miracles there, contradicting Jn2:23 & Jn3:2.
Note: this also applies to the next section 3.9.

Conclusion: there are many clues (plus the observation in 3.1) pointing to the relocation of 'Jesus cleanses the Temple and talks with Nicodemus'.

3.7 The Feast not named:

1) Let's consider:
Jn5:1 "After this there was a feast of the Jews, [many of those occur within one year!] and Jesus went up to Jerusalem."
Comment: all other feasts in Jerusalem, allegedly attended by Jesus, are named: "Tabernacles" (7:2), "Dedication" (10:22) and "Passover" (2:13, 12:1)
Why not this one?

2) Let's also look at:
Jn7:10-11 "... He also went up to the feast, not openly, but as it were in secret. Then the Jews sought Him at the feast [of Tabernacles], and said, "Where is He?""
Comment: why would the Jews at the feast be looking for Jesus if he came "not openly" and unannounced?
Except, of course, if Jesus was already in the vicinity (5:2-47), having just created a controversy by healing a sick man during the Sabbath, as we are reminded:
Jn7:23 "... are you angry with Me because I made a man completely well on the Sabbath?"
That would explain:
Jn7:14 "Not until halfway through the Feast did Jesus go up to the temple courts and begin to teach."

Conclusion: this visit (the second one) to the holy city, 'Jesus heals a sick at a pool in Jerusalem' (5:1-47ff) was extracted from 7:10-^-11. This also complies with the observation in 3.1 and the last comment in the previous section 3.8 (before Jn7:3, Jesus did not go in Jerusalem to perform signs here).
The author did not bother then to give a name for the Feast when he moved the passage.

3.8 The reappearance to Thomas:
Jn20:24-25 "Now Thomas, called the Twin, ... said to them, "Unless I see in His hands the print of the nails, and put my finger into the print of the nails, and put my hand into His side, I will not believe."
Comment: in the gospel and up to that point, there is NO mention about Jesus being nailed on the cross (the same for the rest of the N.T.). If the author had planned to include the passage about 'Thomas looking for nail marks', nailing would have been reported at the crucifixion.

Jn20:24 "Now Thomas, called the Twin, one of the twelve, was not with them when Jesus came."
Comment: there is no comment about Thomas being absent at the first reappearance to the disciples (Jn20:21-23).

Note: in Jn20:19 "when the doors were shut where the disciples were assembled [or gathered]" at the first reappearance. But in some of the most ancient manuscripts (NU-Text), "assembled" is omitted. Would it be an attempt to remove the impression that all the (eleven) disciples (allegedly) were there?
Furthermore, in the corresponding passage of GLuke (which "John" knew and loosely copied, as I will show later), it is specified "the eleven" (the twelve, including Thomas, but minus Judas) are present (Lk24:33).

Proposed solution: 'Jesus reappears to Thomas and again to the other disciples' was not anticipated and added later (as per 3.6), after the first reappearances (20:11-23).

3.9 God/Jesus raising the dead and the believers in the Son will_not/may die:
Jn5:21 "For as the Father raises the dead and gives life to them, even so the Son gives life to whom He will."
Comment: this is the only place where the father is said to raise the dead. The father gives life, the Son can do the same but the mention 'Jesus can raise the dead also' is conspicuously lacking.

Now, let's consider:
Jn8:51 "Most assuredly, I say to you, if anyone keeps My word he shall never see death."
Jn3:15 "... whoever believes in Him should not perish but have eternal life."
Jn3:16 "... His only begotten Son, that whoever believes in Him should not perish but have everlasting life."
Jn10:27-28 "My sheep hear My voice, and I know them, and they follow Me. And I give them eternal life, and they shall never perish;"
Jn6:47-51a "Most assuredly, I say to you, he who believes *in Me has everlasting life. I am the bread of life.Your fathers ate the manna in the wilderness, and are dead. This is the bread which comes down from heaven, that one may eat of it and not die. I am the living bread which came down from heaven. If anyone eats of this bread, he will live forever ..."
Comments: those "Johannine" Christians (who believe in the pre-existent Son) will not become dead, in contrast with the Israelites of Moses (they did die!). It is undeniable here the believers will not perish.

Note: this notion may look extreme and implausible, but in those days, among certain heretic groups, it was NOT so:
According to Eusebius, 'The History of the Church', 3, 26, (placing Menander in the 70-117C.E. period) quoting Justin Martyr, a mid-2nd century Christian, 1Apology, 26:
"Another Samaritan, called Menander ... even persuaded his followers that they would not die: and there are still some [generation(s) later!] who on the strength of his assertion maintain this belief."
And from Irenaeus, 'Against Heresies', I, 23:
"his disciples [Menander's ones] obtain the resurrection by being baptized into him, and can die no more, but remain in the possession of immortal youth"
Furthermore, the uncanonical gospel of Thomas entertains the same concept (details in "The gospel of Thomas").

But, in total contrast, as in the next quotes, it is implied the believers, even if they have everlasting life, will die anyway.
Jn5:28b-29 "... all who are in the graves will hear His voice [of the Son] and come forth; those who have done good, to the resurrection of life, ..."
Jn6:40 "... everyone who looks at the Son and believes in him shall have everlasting life; and I will raise him up at the last day."
Jn6:54 "Whoever eats My flesh and drinks My blood has eternal life, and I will raise him up at the last"
Comment: how odd, to stress eternal life without perishing for the believers (as quoted in the preceding paragraphs), when next their future physical death is predicted!
And let's note also the Son has become the one raising the dead.

Proposed solution: the original gospel did not have 'Jesus raising the dead' or acknowledgment the believer may die. That was added/inserted later.

Note: as I explain later in the "Additions to the original John's gospel", the resurrection of Lazarus (Version 2, 11:1-44) appears to be the turning point from the concept 'the "Johannine" Christians do no perish' to the one where they may die but will be resurrected (by Jesus himself, not by God, as in Jn5:21!):
Jn11:24-26 "Martha said to Him, "I know that he [Lazarus] will rise again in the resurrection at the last day". Jesus said to her, "I am the resurrection and the life. He who believes in Me, though he may die, he shall live. And whoever lives and believes in Me shall never die. Do you believe this?""

3.10 The false ending:

1) Jn20:30-31a "And truly Jesus did many other signs in the presence of His disciples, which are not written in this book; but these are written that you may ..."
Comment: if up to that point, "many other signs" "are not written in this book", why is one of those "unwritten" ones (the miraculous fishing 21:6-11) written afterwards?

2) Jn21:24 "This is the disciple who testifies of these things, and wrote these things; and we know that his testimony is true."
Comment: one of the "we" wrote the "epilogue". But the rest of the gospel is suggested written (earlier) by someone else.

3) Jn20:30-31 "And truly Jesus did many other signs in the presence of His disciples, which are not written in this book; but these are written that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in His name."
Comment: the two verses preceding the "epilogue" look to have been a conclusion for the whole gospel.

Proposed solution: the "epilogue" (21:1-25ff) was written some time after the rest, and by a different author.

Notes:
a) The "epilogue" has synoptic affinities which do not show in Jn1-20, such as the 'sons of Zebedee' (Jn21:2) and the disciples' fishing (Jn21:1-3). Twenty-eight words in the "epilogue" do not appear elsewhere in GJohn, but they do in GMark & GLuke.
b) The epilogue did not show in all copies of GJohn at the end of the 2nd century and beginning of the 3rd. This is according to:
- Irenaeus' Against Heresies (175-185), IIII,14,3 "All things of the following kind we have known through Luke alone (and numerous actions of the Lord we have learned through him, which also all notice): the multitude of fishes which Peter's companions enclosed, when at the Lord's command they cast the nets [Irenaeus did not seem to be aware of Jn21:6,11. And nowhere in his works did he mention anything from Jn21] ..."
- Tertullian's Against Praxeas (200-220), XXXV,17-18 "Wherefore also does this Gospel, at its very termination, intimate that these things were ever written, if it be not, to use its own words, "that ye might believe that Jesus Christ is the Son of God" [Jn20:31] ?" (but in 'A Treatise on the Soul' 50, Tertullian was then aware of Jn21; ditto for the author of the Diatessaron (170-180))

4. Luke's gospel and GJohn:

4.1 The anointment in Bethany, on the feet, by Mary (with Martha), with wiping by means of her hair (Jn12:1-8):
It is a conflation of:
a) Lk10:38-42: at the home of "Martha" and her sister "Mary" (but NOT specified in Bethany, and NO anointment here)
b) Mk14:3-8: when "reclining at the table", anointment in "Bethany" by a woman, with "pure nard", an "expensive perfume" (but NOT on the feet (on the head instead), NO "Martha" and "Mary", and NO wiping with the woman's hair)
c) Lk7:36-38: a woman "poured it on Jesus' feet and wiped his feet with her hair" (but NOT specified in Bethany, and NO "Martha" and "Mary", and NO "pure nard")

Conclusion: "John" had to know both gospels then.
'The anointment in Bethany' was inserted after GLuke became known.

Notes:
A) Could "Luke" have extracted items from GMark & GJohn when writing 10:38-42 & 7:36-38? That can be debated but highly unlikely, more so because the woman of Luke's anointment is not named. And if "John" knew of 'Acts' before his gospel was released, that would remove the possibility "Luke" was aware of GJohn when writing GLuke (considering 'Acts' was written after the later gospel).
B) Let's notice other similarities between GMark & GJohn:
Mk14:4-8 ""Why was this fragrant oil wasted? For it might have been sold for more than three hundred denarii and given to the poor." And they criticized her sharply. But Jesus said, "... Let her alone. Why do you trouble her? She has done a good work for Me. For you have the poor with you always, and whenever you wish you may do them good; but Me you do not have always. She has done what she could. She has come beforehand to anoint My body for burial.""
Jn12:5-8 ""Why was this fragrant oil not sold for three hundred denarii and given to the poor?" ... But Jesus said, "Let her alone; she has kept this for the day of My burial. For the poor you have with you always, but Me you do not have always.""

Remarks:
a) GMatthew (& GLuke) has NO mention of "three hundred dinarii".
b) In GMark (14:3-9), the whole flask is emptied (by a woman) on Jesus' body (naked? If not, the oil would drip on the clothes!), by pouring it on his head (how would that work???), all of that in order to prepare him (still alive!) for burial several days before the crucifixion!!! "John" avoided these absurdities and the perfume is suggested (see bolded italics), for the most part, kept for the day of burial. It seems here "John" was trying to "correct" a very flawed (& highly unrealistic, therefore fictional) passage of GMark. Let's also notice this woman and/or what remains of her oily perfume are not involved in Jesus' burial (Jn19:38-42). Why? Because the later was written earlier (version 1)!

C) In GLuke (7:36-50), the anointment is performed when Jesus goes towards Jerusalem (but before he reaches Jericho). In GMark (14:3-9), it is done after the "triumphal entry". In GJohn (12:2-8), it happens in between, that is one day before Jesus is welcome in the holy city.
D) In GMark, the anointment is in Simon the Leper's house (14:3). In GLuke, it occurs (but very differently) in the home of a Pharisee named Simon (7:39-40). Did "John" get his cue from "Simon" and then proceeded to combine the two stories into one?

4.2 Jesus resurrects Lazarus (11:1-57):
Another passage featuring "Martha" and her sister "Mary" is 'Jesus resurrects Lazarus'.
Furthermore, let's note there is no mention of any Lazarus' resurrection story in the other gospels. However in GJohn, this alleged event is paramount. It explains the triumphal welcome:
Jn12:17-19 "Therefore the people, who were with Him when He called Lazarus out of his tomb and raised him from the dead, bore witness. For this reason the people also met Him, because they heard that He had done this sign.
The Pharisees therefore said among themselves, "You see that you are accomplishing nothing. Look, the world has gone after Him!"
It also starts the plot to kill Jesus (Jn11:45-50). Then, why did the three synoptic gospels NOT report on something so much public & important?

Note: the name 'Lazarus' appears in GLuke, as the beggar in a parable (Lk16:19-31).

The original GJohn did not have any story about the earthly Jesus resurrecting anyone. GMark features one (the little girl of Jairus Mk5:22-43), but the disciples (and parents) are told to keep it secret (against the fondness of "John" for widely witnessed signs!):
Mk5:43a "But He commanded them strictly that no one should know it, ..."
However, GLuke has a very public resurrection observed by crowd and disciples (the widow's son in Nain Lk7:11-17):
Lk7:14b-15a "... He said, "Young man, I say to you, arise."So he who was dead sat up ..."
Let's notice here some similarities with Lazarus' resurrection narrative:
Jn11:43b-44a "... He cried with a loud voice, "Lazarus, come forth!" And he who had died came out ..."

Conclusion: because of "Martha" & "Mary" and some similarities with GLuke 7:11-17, 'Jesus resurrects Lazarus' (11:1-57) and also 'Lazarus is remembered' (12:17-19) were added on after GLuke appeared.

4.3 The Samaritan woman (4:1-42):
Two of the main characteristics of GLuke are its pro-women and pro-Samaritan stances.
On the former, I urge you to consult this page where I listed all my (many) arguments proving the point. Here, my main conclusion is that "Luke" was a Christian woman from Philippi, addressing a community traditionally led by women.
On this other page, I explained Luke's interest with Samaritans: they were used as substitutes for Gentiles (the later not known to have been preached by Jesus).

Then what do we have in 'the Samaritan woman' passage?
a) A friendly one to one conversation, with the Samaritan woman looking more and more like a Gentile Christian convert. It is also stressed here the Samaritans are NOT Jews:
Jn4:9 "... "How is it that You, being a Jew, ask a drink from me, a Samaritan woman?" For Jews have no dealings with Samaritans."
Jn4:20 "Our fathers worshiped on this mountain, and you Jews say that in Jerusalem ..."
b) Many other Samaritans rally around Jesus (and become Christians!):
Jn4:39-42 "And many of the Samaritans of that city believed in Him ... So when the Samaritans had come to Him, they urged Him to stay with them; and He stayed there two days. And many more believed because of His own word. Then they said to the woman, ... we know that this is indeed the Christ, the Savior of the world.""

It looks "John" used the same stratagem as "Luke" did, by featuring Samaritans as non-Jews (= Gentiles). What a contrast with the rest of the gospel where Jesus meets disbelief and hostility from the Jews at large! And with the Samaritans, there is no need for performing sign(s) to attract their attention!
The main point of the Samaritan episode is as follows:
If Jesus had dealt with Gentiles, instead of those "stubborn" Jews, he would have been believed, as he (allegedly) did with the Samaritans!
Furthermore, "Luke" gave the impression, that in order to go from Galilee to Jerusalem (Judea), one has to go through Samaria (which is not true):
Lk9:51b-52a "... Jesus resolutely set out for Jerusalem. And he sent messengers on ahead, who went into a Samaritan village ..."
And in GJohn, we have:
Jn4:3-4 "He left Judea and departed again to Galilee. But He needed to go through Samaria."

Conclusion: because of the aforementioned and 3.2, 'the Samaritan woman' was added on after GLuke got known.

Note: "John" (and his community) did not seem to know about GMatthew:
Mt10:5 "These twelve Jesus sent out with the following instructions: "Do not go among the Gentiles or enter any town of the Samaritans.""

4.4 The nobleman's son (4:43-53):
This story is very similar to the one of the centurion's servant in Lk7:2-10:
a) The healing is performed remotely.
b) The healing occurs in Capernaum.
c) The master/father is someone with authority.
Note: 'nobleman' is also translated by 'royal official'.
Why would a centurion be replaced by a royal official?
It did not make any sense for a foreign (as implied in Lk7:5, presumably Roman) centurion to have a house in Capernaum. Galilee, ruled by a client king, was not even under direct Roman control.

Conclusion: because of some similarities with GLuke, but mostly due to 3.2 (confirmed by 4.3), 'the nobleman's son' was added later.

4.5 Jesus and John the Baptist (3:22-36):
Jn1:25-26a "And they asked him, saying, "Why then do you baptize if you are not the Christ, nor Elijah, nor the Prophet?" John answered them, saying, "I baptize with water, ..."
John the Baptist (JohnB) has already been introduced as NOT Christ, NOT Elijah and NOT the Prophet. His baptizing is on his own decision, NOT responding to God's call. Furthermore, he declared already his great inferiority compared to Christ:
Jn1:27 "It is He who, coming after me, is preferred before me, whose sandal strap I am not worthy to loose."

Then why bother going to another session (Jn3:26-31) like the last one (Jn1:15-27)?
Jn3:28 "You yourselves bear me witness, that I said, 'I am not the Christ,' but, 'I have been sent before Him.'"
Jn3:30-31a "He must increase, but I must decrease. He who comes from above is above all ..."
But there is more: Jesus is baptizing too, and beating JohnB at his own game:
Jn3:26 "And they came to John and said to him, "Rabbi, He [Jesus] who was with you beyond the Jordan, to whom you have testified; behold, He is baptizing, and all are coming to Him!""
Why this second passage about JohnB, downgrading him even further?
It may have been caused by the author's reaction against:
Lk3:15 "Now as the people were in expectation, and all reasoned in their hearts about John, whether he was the Christ or not"
Lk3:15 may have renewed beliefs in the community about JohnB as the Christ, that the author wanted to extinguish!

Conclusion: because of my last comment and the repetitions (with Jn1:19-26), but mostly due to 3.2 (confirmed by 4.3), 'Jesus and John the Baptist' was added on later.

4.6 Jesus reappears to Mary Magdalene and the disciples (20:11-23):

1) Let's consider first the reappearance to the disciples:
Jn20:19-21a "Then, the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled, for fear of the Jews, Jesus came and stood in the midst, and said to them, "Peace be with you." When He had said this, He showed them His hands and His side. Then the disciples were glad when they saw the Lord. So Jesus said to them again, "Peace to you! ...""
Comment: let's notice the similarities (& differences) with the first part of Luke's apparition to the disciples:
Lk24:36-39a "Now as they said these things, Jesus Himself stood in the midst of them, and said to them, "Peace to you." But they were terrified and frightened, and supposed they had seen a spirit. And He said to them, "Why are you troubled? And why do doubts arise in your hearts? Behold My hands and My feet ..."" (the words in italics may be an interpolation because not showing in some ancient manuscripts)

Furthermore, in the same passage:
Lk24:49a "Behold, I send [notice the present tense] the Promise of My Father upon you;
[there is no prior mention (& identification) of this "Promise". But "upon [someone]" is associated with the Holy Spirit in Lk1:35,2:25,3:22,4:18. Also the "Promise" could be a reference to Joel2:28-29 "... I will pour out My Spirit on all flesh; ...And also on My menservants and on My maidservants I will pour out My Spirit in those days [before the "day of the Lord" (2:31)]." (as quoted in Ac2:17-18)] ..."
Comment: it does seem here the Spirit is delivered to the disciples "on the spot". And "John", not knowing of 'Acts' and the Pentecost event, had also the Holy Spirit given to the disciples right away:
Jn20:21b-22 ""... As the Father has sent Me, I also send you." And when He had said this, He breathed on them, and said to them, "Receive the Holy Spirit ...""

2) Even if the resurrected Jesus does not appear first to women in GLuke, the reappearance (the first one in GJohn) to Mary Magdalene fits well with the pro-woman stance of the third gospel. Here, let's also notice the status of MaryM is enhanced (Lk8:2). There are also some similarities with 'Jesus and the two disciples on the road to Emmaus' passage (Lk24:13-34), the first narrated reappearance in GLuke:
a) At first, Jesus is thought to be a stranger (Lk24:16, Jn20:14,15a).
b) They/she hurry(ies) to the disciples with the (good) news (Lk24:33,35, Jn20:18).

Notes:
a) At the empty tomb, there is one angel in GMark (16:5-7) and GMatthew (28:2-7), but there are two angels in GLuke (24:4-7) and GJohn (20:12-13). This is an additional indication "John" knew then about Luke's gospel.
b) Mary Magdalene appears abruptly in Jn19:25 & Jn20:1, without any description about her. Would that suggest this woman was already known in John's community through GMark (15:40-41) and GLuke (8:1-3), and consequently not requiring a presentation? More so when we consider "John" did not mention why this Mary would know about the (correct) tomb (but GMark (15:47) & GLuke (23:55) explained it!).

Conclusion: because of similarities with GLuke, and also of 3.4, 'Jesus reappears to Mary Magdalene and the disciples' was added on later.

Note: how to explain the later inclusion of women in GJohn?
It appears the original version had Jn2:4-5 as the only passage where Jesus is dealing with a woman, here his own mother:
Jn2:4a "Jesus said to her, "Woman, what does your concern have to do with Me?"
With "woman", the author intended to show that Jesus, as an immortal divine entity, considers his mother as a mortal female, the equivalent of the ninety-three "son of man" in 'Ezekiel'.
However, many Christian women then might have not known about the theological subtlety, and consequently disliked the whole gospel and its "Jesus": any mother would consider an insult to be called "woman" by her son!
Then came GLuke, with its pro-Mary & pro-woman stances, which must have appealed to the local female believers, another good reason for them to reject GJohn.
However, it seems "John" tried later to remedy to the initial "faux pas":
a) In Jn20:13, MaryM is called "woman" by angels, as to reiterate the theological connotation of "woman", as said by a heavenly entity.
b) In Jn20:15-16 MaryM is also addressed as "woman" by the resurrected Jesus, but next he calls her "Mary". Then MaryM says "Rabboni" (dear teacher), seemingly not offended by "woman"!
c) Jn20:17b "... 'I am ascending to My Father and your Father, and to My God and your God.'"
Here the status of MaryM, a woman, is elevated to the one of the Son of God himself!
d) In the 'below the cross' passage (Jn19:25-27), Jesus addresses his mother again as "woman", but immediately after "lowers" himself by declaring he is her son:
Jn19:26b-27a "He said to His mother, "Woman, behold your son!" Then He said to the ["beloved"] disciple, "Behold your mother!""
Here, Jesus assigns Mary to his best disciple, proving he cares about his mother, even if he keeps calling her "woman"!
Because of the aforementioned, and also the presence of two other women, I think Jn19:25:27 is "post-Lukan" and was not part of the original gospel.
Furthermore, in GMark (or GMatthew & GLuke), there is no mention of family members or disciples witnessing the crucifixion.

5. 'Acts' and GJohn:

5.1 Jesus reappears to Thomas and again to the other disciples (20:24-31):
In this short passage, there are three things which appear here, but are not in GLuke but present (or suggested) in 'Acts':

a) The long reappearance period:
The second reappearance to the disciples (with Thomas this time) happened one week after the first one. However the impression given by GLuke24:36-49 is that the reappearance to the disciples was short. And immediatly after, Jesus (and company) goes towards Bethany and he ascends to heaven: no second reappearance possible one week later!
However in 'Acts', we have, and before the ascension occurs (again!):
Ac1:3 "to whom [the apostles] He also presented Himself alive after His suffering by many infallible proofs, being seen by them during forty days and speaking of the things pertaining to the kingdom of God."
That would open the possibility for a second reappearance to the disciples (including Thomas) one week later!

b) Other signs during the reappearance period:
Jn20:30 "And truly Jesus did many other signs in the presence of His disciples ['disciples' for "John" means members of the twelve and other close followers/believers], which are not written in this book;"
Comment: isn't it reminiscent of "presented ... many infallible proofs [to his "apostles" (1:2), during the forty days after his first reappearance]", from Ac1:3, previously quoted?
Let's note also these latter signs are performed amidst the disciples only, not among other (unfriendly) Jews as before the crucifixion. Once again, this is very much according to:
Ac10:40-41 "Him God raised up on the third day, and showed Him openly, not to all the people, but to witnesses chosen before by God, even to us [the eleven] who ate and drank with Him ..."

c) Jesus nailed on the cross (a weak point, I concede):
Jn20:25 "... Unless I [Thomas] see in His hands the print of the nails, and put my finger into the print of the nails, ..."
Let's consider:
Ac2:23 "Him, being delivered by the determined purpose and foreknowledge of God, you have taken by lawless hands, have crucified [affixed], and put to death;"
The Greek word for "crucified", which normally (according to Paul's letter and the gospels) would have been used here, is replaced by a derivation from PROSPHGNUMI "fastened/affixed", which occurs only here in the N.T. Nailing is not necessarily inferred even if some bibles (such as the NIV & NASB) do translate it as "nailed" (on the cross).

Notes:
a) "On the cross" does not appear in the Greek, just "affixed".
b) The "thrust" of "affixed" is on the fastening (of Jesus on the cross) and not on the long process of crucifixion -- including going through an excruciating agony and finally dying -- as "crucified" entails. Actually, the dying is covered by "put to death [or slain]"
Therefore, there is some probability "John" would have gone one step further from the "affixed" of 'Acts' and postulated "nailed".

Conclusion: because of the previous discussion, and also from 3.5 & 3.8, 'Jesus reappears to Thomas and again to the other disciples' was added on later, after 'Acts' became known.

5.2 Miscellaneous:
In other parts of GJohn, other clues suggest "John" knew then about 'Acts':

a) The visible ascension:
Jn6:62 "[to his disciples] What then if you should see the Son of Man ascend where He was before [in heaven]?"
Here is a clear indication of the ascension (not mentioned in GMark & GMatthew).
In Lk24:50-53, it is not specified the disciples see the ascension, narrated briefly as "He was parted from them and carried up into heaven". But in 'Acts', they do see it:
Ac1:9 "... they [the disciples] watched, He was taken up, and a cloud received Him out of their sight."
Furthermore, Jn6:62 appears to be an inserted digression, not related at all to the main topic.

b) Jesus as the Judge:
Unlike Paul's letters, 'Hebrews', 'James', GMark, GLuke (but not GMatthew), 'Acts' features Jesus as the Judge:
Ac10:42 "... He [Jesus] who was ordained by God to be Judge of the living and the dead."
Jesus as the Judge also appears in a small section of GJohn:
Jn5:22 "For the Father judges no one, but has committed all judgment to the Son,"
Jn5:27 "[the Father] has given Him authority to execute judgment also, because He is the Son of Man."
Jn5:30 "... As I hear, I judge; and My judgment is righteous, ..."
However somewhere else:
Jn12:48 "He who rejects Me, and does not receive My words, has that which judges him; the word that I have spoken will judge him in the last day."
Here, it is not Jesus who will judge "in the last day", but "the word that I have spoken", suggesting Jn5:22-30 was written later. Furthermore, it does not appear Jesus would be the Judge in this verse:
Jn8:50 "And I do not seek My own glory; there is One who seeks and judges"

Note: Jesus will judge and raise the dead (5:25-30):
As discussed before, this small passage includes 'Jesus as the Judge', but also:
Jn5:25 "Most assuredly, I say to you, the hour is coming, and now is, when the dead will hear the voice of the Son of God; and those who hear will live."
Jn5:28-29 "Do not marvel at this; for the hour is coming in which all who are in the graves will hear His voice and come forth; those who have done good, to the resurrection of life, and those who have done evil, to the resurrection of condemnation."

Conclusion: because of the previous discussion, and also 3.9, 'Jesus will judge and raise the dead' was added on later, after GLuke was known, and then after 'Acts' appeared. Please also note the raising of Lazarus cleared the way for 'Jesus raising the dead'.

5.3 Jesus reappears to some disciples in Galilee (21:1-25):
The author of the epilogue did not know (or rejected) 'Acts':

a) Jn21:14 "This is now the third time Jesus showed Himself to His disciples after He was raised from the dead."
In 'Acts', Jesus shows himself many times to his disciples during a forty days period:
Ac1:3 "to whom [the disciples] He also presented Himself alive after His suffering by many infallible proofs, being seen by them during forty days and speaking of the things pertaining to the kingdom of God."
b) In Jn21:15-17, Peter is chosen as the shepherd of Jesus' flock, when himself and some disciples are back to Galilee and fishing (complying with Jn16:32, the disowning & dispersion home).
However in 'Acts', the church of Jerusalem is started by Peter, with himself as the leader, before the disciples have a chance to go back to Galilee (which is never mentioned in 'Acts').

Conclusion: because of 3.10 and the aforementioned comments, the "epilogue", 'Jesus reappears to some disciples in Galilee', can be confirmed to have been written some time after the rest, and by a different author. This author did not know (or rejected) 'Acts' (but certainly he was aware of GLuke & its miraculous fishing 5:1-11).

6. What's next?
On this next (and short) page, the gospels according to John, I'll define the nine "blocks" of the original gospel and then the later versions, with the different additions & relocations, by blocks again; and all along complying scrupulously with what has been concluded here. Included are the first and last verses of each block, in order to show the interconnections.