Does "open in disposable VM" from modifying the original file?

[Tai...@gmx.com]

Assuming you don't make any changes yourself, it would also be nice to
have a "yes/no" popup so you can choose as to if you wish to have a
truly disposable version.

[Unman]

I'm not quite sure what your point is, because there's a word missing
from the subject line. (Could it be "prevent"?)

There's an interesting discussion on this at qubes issues:
https://github.com/QubesOS/qubes-issues/issues/1118

If you don't make a change yourself the file wont be changed in the
sender qube. Saving a file in the disposableVM provides the yes/no
prompt you are asking about.

unman