Vivaldi file picker crash

After changing my desktop from herbstluftwm/X11 to sway/Wayland on my Linux system, the Vivaldi file picker download broke. The dialog itself was fine but after a file was selected the dialog would close and the browser would crash with a segmentation fault. Turns out the problem was in the machinery the browser uses to talk to the windowing toolkit.

This also seemed to cause problems with downloading files sometimes (i.e. the download button inside the PDF viewer)

After installing xdg-desktop-portal and xdg-desktop-portal-gtk, using the default Sway configuration, then running systemctl restart –user xdg-desktop-portal, everything seems to play nicely.

The xdg-portal parts seem to be built for pre-packaged app blobs rather than stand-alone apps but for some reason Vivaldi uses them.