Chrome was updated September 11
Matrix Element Desktop updated September 15, without a changelog or advisory. (The Element update on September 13 did not include the updated electron with the fix; today’s update does, according to their announcement on Matrix.)
Many/most electron apps don’t receive timely security updates, so if you don’t want arbitrary images to be able to get code execution you might want to stop using them.
https://github.com/uazo/bromite-buildtools/issues/59
https://github.com/uazo/bromite-buildtools/issues/41
Edit: also:
https://github.com/uazo/cromite/issues/146
Okay