Fix multi-select values in metadata not removable (Safari)

[Arnei]

Fixes a bug where values could not be removed from multi-select fields, like presenters or contributors in the event metadata. When clicking on the "X" of the blue box with the value, the field would leave edit mode but the value was not removed. This is due to a timing issue most notable in Safari. This patch fixes the issue by making the field not leave edit mode when clicking on "X", which is how multi-select fields behaved in 18.x as well.

This fix has an unpleasant side effect, where multi-select fields will not properly blur anymore when left via tab navigation. I am not sure how to properly fix this with the current code.

[github-actions]

Use docker or podman to test this pull request locally.

Run test server using develop.opencast.org as backend:

podman run --rm -it -p 127.0.0.1:3000:3000 ghcr.io/opencast/opencast-admin-interface:pr-1496

Specify a different backend like stable.opencast.org:

podman run --rm -it -p 127.0.0.1:3000:3000 -e PROXY_TARGET=https://stable.opencast.org ghcr.io/opencast/opencast-admin-interface:pr-1496

It may take a few seconds for the interface to spin up.
It will then be available at http://127.0.0.1:3000.
For more options you can pass on to the proxy, take a look at the README.md.

[github-actions]

This pull request is deployed at test.admin-interface.opencast.org/1496/2026-01-05_11-52-27/ .
It might take a few minutes for it to become available.

[gregorydlogan]

This doesn't break anything obvious to me, but I don't have a Mac to test with. @mtneug @karendolan @rute-santos @snoesberger I think you're all on macs. There's a test above, don't even have to build anything.

[snoesberger]

I did a quick test on my Mac using Safari. I can now successfully remove values from the multi-select fields. I also successfully tested this with Firefox and Chrome.

But I had to use the docker image to test this. test.admin-interface.opencast.org/1496/2026-01-05_11-52-27/ doesn't allow me to change metadata because of CORS policy:

Access to XMLHttpRequest at 'https://develop.opencast.org/admin-ng/event/ID-portrait/metadata' from origin 'https://test.admin-interface.opencast.org' has been blocked by CORS policy: Method PUT is not allowed by Access-Control-Allow-Methods in preflight response

It would be nice if the CORS policy could be adapted to allow such tests.