Whilst adding tags to a variety of test files I came across one that appears to be untaggable. The same file accepts comments and star rating but steadfastly refuses to accept tags. There is no error message when Apply is clicked. I tried copying the file to another local location but the same thing happens there. As a further test I then zipped, copied to another PC, unzipped and tried again. On the second system there was no problem!
This seems to be a weird one-off and is an oddity rather than a concern but if there is some way of debugging this on the system where the problem manifests I would be happy to try. Both PCs are running Windows 10 Pro version 1909 OS build 18363.1139 and Opus v12.22.
Since it's a .exe file, and works on another machine, it could be due to antivirus.
Could also be the type of drive the file is stored on, since adding tags to a .exe will require placing them into NTFS ADS (since the content of the .exe itself can't be touched).
After debugging with AlternateStreamView I have pinned down the culprit. The untaggable EXE is actually DOpusinstall.exe for v12.22. Somehow I have multiple copies of this executable, superficially identical. On closer inspection the one that is untaggable has four ADS data streams and the one that is taggable has three. See below. If I make a duplicate copy of the untaggable EXE and use AlternateStreamViewer to delete the highlighted SummaryInformation stream the resultant EXE becomes taggable with Opus.
If that file had already been tagged with one of the recent betas, and the issue was that changing the tags didn't work, that was most likely due to an unintentional change in the way the recent betas wrote tags, which has been fixed in 12.22.
If it was that, you shouldn't run into the issue again with new files, but may need to clear out the ADS on any others tagged with the same version.
Removing the SummaryInformation ADS should be sufficient.