This area of the code was recently worked on in T265716. CC @Scardenasmolinar @jsn.sherman

This seems to also be fixed by 1163068 Leave watchlist expiry unchanged when param is omitted in API calls (my patch for T397226).

…And the reason that fixes it is that the VE API actually does not have a parameter to set the watchlist expiry. The VE frontend passes the value in the wpWatchlistExpiry parameter, which then passes transparently through all the API layers (which all think that the expiry parameter was omitted), and which is handled directly in EditPage. This seems like a bug, and it just works due to a series of lucky accidents :)

Tried a patch demo (https://patchdemo.wmcloud.org/wikis/2e61fc2ecf/) and it doesn't seem to have fixed it

Change #1165010 had a related patch set uploaded (by 1F616EMO; author: 1F616EMO):

[mediawiki/extensions/VisualEditor@master] ext.visualEditor.articleTarget: Corrects the POST key of wpWatchlistExpiry

https://gerrit.wikimedia.org/r/1165010

Change #1165010 merged by jenkins-bot:

[mediawiki/extensions/VisualEditor@master] ext.visualEditor.articleTarget: Corrects the POST key of wpWatchlistExpiry

https://gerrit.wikimedia.org/r/1165010

Thanks for checking @Pcoombe and thanks for the patch @1F616EMO. My change has fixed using the default expiry time from preferences, but it didn't fix choosing one in the dropdown while editing. Now both should be fixed.

I found a failing post-merge build: https://integration.wikimedia.org/ci/job/mwext-codehealth-master-non-voting/75504/console. Are there anything I should do?

In T397709#10982971, @1F616EMO wrote:

I found a failing post-merge build: https://integration.wikimedia.org/ci/job/mwext-codehealth-master-non-voting/75504/console. Are there anything I should do?

This is a non-voting check, so it's ok to have it failed. No action needed.