The integrations folder button opens a folder

The button beside the folder for your own integrations did nothing on a fresh profile, because the folder did not exist and the shell's error was thrown away. It creates the folder first, and says so when it cannot.

On a fresh profile, the button that opens the folder for your own integrations did nothing when clicked, and said nothing either.

The folder does not exist until someone makes it, shell.openPath answers a missing path with an error string rather than a rejection, and PlatformService.openPath threw that string away. The button now creates the folder first, and a failure it can see raises a notification naming the path.

• A failure after the folder exists is still invisible, because PlatformService.openPath returns nothing. Surfacing it means changing that platform API.
• The suite stubs the open call, so it proves the folder is created and handed over, not that Explorer appears.