TagFormat is not working properly

[ischowam]

I spent some time on clicking through the folders and comparing the files and the content of the folders, if seeing the year or not.

I recognized the following, which I can reproduce meanwhile:
If there are files in one folder with different album-names, the year is displayed.
If all have the same album-name and all files have different tags, the year is not displayed.

Examples:
I do not use the disc-no-tag, but usually put all tracks of a double-album into one folder and add a "CD1" or "CD2" to the album-name > year is displayed

There is a mix of tracks from various albums in one folder > year is displayed

If there is a Bonus-Disc, I put a "(Bonus)" or similar to the album-name > year is displayed

An interesting example:
All files have the same album-name.
Two files have exactly the same tags, but different files names (I wrongly tagged hidden files in the same way as the last unhidden track) > year is displayed
After correcting the tag of the hidden file, so that all files have different tags > year is not displayed anymore

That aso explains why I sometimes at first saw the year for a moment: it took a second to scan all tags.

So far so good.
But why is Bubble behaving like this?
I guess I need to switch to a Bubble-Forum now unless someone here has a solution how to prevent this. :-)