It is not a question of copy or move.
Besides the features of copy and move (known from the explorer) there is also a feature of delivering one or more files to another apllication for further treatment.
Most of the software I use (players, graphic software, Editors, Office ...) is able to handle that and I never before saw that this D&D had any influence on the source.
That Mp3Tag acts like this has certainly to do with the other software. You can also see that because it does not happen with all software and it is different
ie. it happens with
- Audacity but can be avoided with CTRL
- Mp3 Quality Modifier (cannot be avoided)
and it does not happen with
- Players I know
I think the correct behaviour would be that it does not happen at all while delivering files to other apllications (which has nothing to do with copy and move).
That it is not completely dependend on the receiving piece of software is observable with Foobar that does not behave like this with MP3 Quality Modifier.
The problem of showing files with perhaps changed data cannot be avoided by hiding these files after D&D. This problem is always immanent and to really avoid it you would have to use a watchdog that registers every change of the loaded files.
MP3Tag has no influence what other software does with its loaded files.
Even if the files have vanished in the list view after D&D you can get them back with a refresh and afterwards modify them them with the receiving software.
And you can load these files directly (without D&D) with other applications to treat them while they are also loaded and displayed in MP3Tag.
And even software like players or. i.e. MP3DirectCut with which MP3Tag does not hide delivered files after D&D are able to change the delivered data and MP3Tag will only notice this with a refesh.
All this shows that hiding files after D&D is not suitable as protection mechanism.
It is only an unexpected behaviour that should be avoided if possible.