Electron snap killed when using app.makeSingleInstance API

snapd
17

I tried to provide that insight. There are only two ways this should be happening:

you enabled the chromium setuid sandbox and so it is starting as root. When I did the snap-review tool, it didn’t complain about setuid binaries, so this probably isn’t it you are using ‘daemon’ as one of your commands which creates the socket as root

Hey thanks for the reply!

  • I’m not using a daemon command. The snapcraft.yaml file is linked in my original post and only contains the app command.

  • I’ve verified that I am not enabling the Chromium sandbox. (It looks like --no-sandbox is the default now so passing it isn’t necessary [commit], and turning it on explicitly via mailspring --enable-sandbox causes the app to immediately crash. )

Since this bug is only exhibited when I use Electron’s app.makeSingleInstance API, I’ve updated the post title to reflect that and I’m going to keep digging in there.

I downloaded a few other Electron snaps and I’ve found the same problem occurs with mattermost-desktop, brave and wordpress-desktop. (Launch one and then run the launch command on a second command prompt. The running copy is killed and the new copy starts, which is not intended behavior.) I think it’s just more noticeable in Mailspring because the app is invoked frequently by mailto links. I imagine it will also prevent Brave from handling web links from other apps, though.