Comment 70 for bug 1643706

This has been going on for at least 6 years now! Even though I am not a Ubuntu man (for historical reasons I am on OpenSuse), it is highly relevant to me, because after the latest OS upgrade, my time-honoured Acrobat Reader 9 (Linux version!) can finally not run any more. So I installed the snap "acrordrdc", which runs a more modern version of the Reader.

But, the restrictions discussed here leave an Acrobat Reader under snapd almost entirely useless: when trying to open a PDF file from inside a browser (e.g. Firefox) or a mail program (e.g. Thunderbird), that application will download the file into the /tmp hierarchy and then call the default application for .pdf with that path as an argument.

Which, of course, won't work if I set my snap-based Reader as the default! And loop-back mounting /tmp somewhere in the home directory does not help either, because the pathname passed on to the Reader will still start with /tmp.

I am now working on a work-around wrapper, but that will be a kludge, not a solution.

The whole issue also raises the silly question: what is so security-sensitive about /tmp?