Help:Edit conflict

This page discusses edit conflicts, and how to deal with them. To understand what an edit conflict is, consider the following situation:

At the top of the edit-conflict page is an editing box containing Bob's version of the whole page, even if Alice is doing section editing.

At the bottom of the edit-conflict page is a second editing box containing the text Alice was going to submit. This will be Alice's version of the page or section she was editing.

Between the two editing boxes is a diff that shows the difference between Bob's and Alice's version of the article. For the section Alice is editing it shows Alice's changes and Bob's possible changes, except for sections where Alice and Bob have both made the same change. For the other sections it shows the full new text as if all that text was added.

Alice can edit in the upper editing box and press Save. In the case Alice was editing only a section, this will be interpreted as the new version of the section, hence produce duplication of the other sections, unless Alice deletes them before saving. (This seems to be a bug.) The best solution in this case is to save your new text (e.g., to the clipboard), cancel out, then try again.

At certain times when pressing Save and the system is slow, one may be able to make multiple edits to the same page before the system responds. This produces an edit conflict with oneself. In this case the upper text may be the old version instead of the one involving the first edit, i.e., the system notices the earlier change but has not processed it yet. A moment later, while one is viewing the edit-conflict page, the first change is carried out in the background, and the upper text no longer is the current one. Hence, the diff shows the combined edit, and in the case of section editing, like before, the "addition" of the other sections. If you choose to save your work in this type of edit conflict, it will result in the removal of your previous editing from the page.

If Alice made only small changes, and Bob made large changes, she may choose to work from Bob's version, and re-merge her changes in. Alice might choose to add some text like "via edit conflict" to the edit summary, or use template {{}} on a Discussion/Talk page, to warn Bob and others that she had to do this – Bob can then her merging for accuracy.

If Alice made large changes, and Bob made small changes, Alice may choose to work from her version. One option is for Alice to copy the bottom text into the top text (or just copy over the one section of the top text, if Alice was section editing), with an appropriate edit summary (e.g., "via edit conflict, will remerge"). Then Alice can view the page history, determine Bob's changes, and re-apply them to her version, in a separate edit.

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