User:Furrykef/MediaWiki edit conflict failure

This is a bug regarding the failure of the software (as of MediaWiki 1.17wmf1 (r82948)) to report edit conflicts when the same user edits the same page using multiple tabs using whole-page edits. (I originally thought this applied to edits made by multiple people, which would be a severe bug indeed, but, thankfully, it does not.)

Verifying edit conflicts from same user
First, let's verify that edit conflicts are triggered properly when the same user edits the same section (as opposed to same page) twice using different browser tabs. If this is the case (and it is), edit conflicts can be tested using only one user instead of two. Create a page (e.g. in a sandbox page) with the following contents:

== Testing == This is a test

Save the page. There should be an edit link next to "Test one". Middle-click this edit link (not the one for the whole page &mdash; we'll get to that in a minute &mdash; but rather the section link) twice, creating two tabs. Alter the line "This is a test" in both of them, for example to "Testing" and "Test123", and save both. If done properly, this should trigger an edit conflict, which is the (in my opinion) correct and expected behavior.

Reproducing the bug
Now follow the same procedure as above, but using the edit link for the page, not the edit link for the section. No edit conflict is triggered.

My opinion is that the edit conflict could still be triggered, because I have in fact accidentally edited the same page from multiple tabs before. I wouldn't want my edits to be accidentally reverted by myself (potentially without me ever noticing) any more than I'd want them to be reverted by somebody else, so I think the edit conflict is clearly the correct behavior, despite the edits coming from the same user.