When using JSON:API, it's much easier to use the UUID than the Drupal node ids. However, the Flag module currently requires the Drupal internal id to flag/unflag, which makes it more complicated to build flagging links.
It would be great if there was support for UUIDs like this:
http://example.com/flag/confirm/unflag/my_flag/6aa13a73-09ab-498c-94d0-e...
It will become possible to use the UUID (instead of the drupal internal entity id) for flagging/unflagging.
Needs work
4.0
Flag core
The patch will have to be re-rolled with new suggestions/changes described in the comments in the issue.
The change is currently missing an automated test that fails when run with the original code, and succeeds when the bug has been fixed.
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