pressure-vessel is not cleaning up locale directories in /tmp

On my machine, pressure-vessel does not clean up locale directories in /tmp/, so after a few dozen runs you see:

$ ls /tmp/ | grep pressure-vessel-locale | wc -l
205

I don't have any reason to think it is specific to any game, but I definitely see it with Deus Ex GOTY (6910) and a few other games (e.g. Dead Space (17470), Downwell (360740)) with both Proton 5.13 and Proton Experimental. I haven't yet seen a game that doesn't leave these directories in /tmp/.

This is on an up to date Arch with Steam Beta client.

#Name	Version		Runtime	Runtime_Version	Comment
SteamLinuxRuntime	v0.20210114.1-0-g5a1cbb7			# Entry point scripts, etc.
pressure-vessel	0.20210126.0+srt1	scout	0.20210127.0	# pressure-vessel-bin.tar.gz
soldier	0.20210126.1	soldier	0.20210126.1	# com.valvesoftware.SteamRuntime.Platform-amd64,i386-soldier-runtime.tar.gz

I don't see any crashes in the Steam output, nor in an SLR log.