Comment 21 for bug 1887804

Please see comment #20.

My online backup set specifically excludes $HOME/.cache (the default or unset value of $XDG_CACHE_HOME) to avoid churning backup snapshots with transient application cache data.

I don't know if chromium ever respected $XDG_CACHE_HOME (it would appear from the bug report mentioned in comment #8 that it does not), but in previous packages, it used to store cached data under $HOME/.cache/chromium and now it no longer does. Although it could have been a change in chromium's behavior, the change of location appears to be co-incidental with the transition from deb to snap packaging.

Please note that in the snap packaged version of chromium (build 88.0.4324.96), there is a $HOME/snap/chromium/common/.cache directory, but chromium does not store the bulk of its cache data in that location. Most of the cached data is found in 86 or so various directories under $HOME/snap/chromium/common/chromium/Default .

It is not clear to me that I can reasonably exclude either or both of $HOME/snap/chromium/common/.cache/ or $HOME/snap/chromium/common/chromium/Default/ to achieve the desired result of limiting transient disk cached data from entering the backup snapshots while keeping chromium user configurations backed up.

Since the previous deb packaged version of chromium did store its cached data in the XDG default location (although perhaps only by accident? maybe the deb package maintainer configured it?), and the current snap packaged version does not, I am looking for current package maintainer's guidance on the best way for our backup system to handle this change in behavior.