Hi, I encountered the same issue and narrow it down to the canonicalize function of either async_std or tokio, the issue is chromium is installed through snap and the chromium is a symbolic link to /usr/bin/snap. canonicalize follow the symlink to use the real executable which does not work in this case as snap should not be called directly.
chromium identified first as /snap/bin/chromium

Then canonicalize transforms it to /usr/bin/snap

Only way/Easiest way to handle this is to cancel the canonicalize if the final path is targetting snap, needs to be done/fixed in this plugin, there is no workaround I can think of.

I might give it a shot next year as I won't have access to a computer for the next few days.
Have a good New Year's Eve !