Editing Metadata information in Modern experience

Question

While Trying to Edit the Metadata information in Modern experience in a site pages library Not showing options from metadata list on information pane on right hand side but if i switch to classic site experience and edit it i can see the options

It shows as processing but it takes forever

Answer 1

I could not reproduce your issue per my test.

Make sure that there are no more than 200,000 terms, 1,000 global term sets, and 1,000 groups in the term store.

Then check as follows:

1. Add the managed metadata column in another library then edit it in modern experience to compare the result.
2. Clear the browser cache to check if the issue could be fixed.