This workaround breaks down with dual screens.
There is an option you can change to switch off this workaround. Doing
so will require you to close DeveloperCompanion before the last browser
window otherwise your new browser window comes back in the position and
size of DeveloperCompanion.
To change the option browse to:
about:config
and set:
extensions.devcomp.browserWindowSizingEnabled
to:
false
Its a bad situation that will hopefully be resolved soon.
Thanks for reporting your experience!
Christoph