Window Shuffler seems to hate dots (and probably ignores case sensitivity)

[pillmuncher]

I wanted my Thunderbird to always open on DisplayPort-2 (my primary display) in Workspace 2. When I open the 'Window Shuffler Control' window, go to 'Window rules', and add a new rule, I can put the cursor in the 'WM class group*' input box and put my mouse over the Thunderbird window and 'net.thunderbird.thunderbird' gets inserted. xprop, BTW, tells me that Thunderbird's WM_CLASS is '"Mail", "net.thunderbird.Thunderbird"'. Notice the 'T' instead of a 't'. After I close the 'Add new rule' window, the 'WM-class' entry is set to 'net', not 'net.thunderbird.thunderbird', although the file is created under the correct name under '~/.config/budgie-extras/shuffler/windowrules/'. When I try to modify the entry a new file 'net.windowriule' is created. I've experimented with all sorts of entries like manually entering 'net.thunderbird.Thunderbird' or 'Mail', and with different file names, like 'Mail.windowrule', 'thunderbird.windowrule', and whatnot, but to no avail. The Thunderbird window always opens on the current monitor and active workspace.

Here is the file the Window Shuffler Control has generated
~/.config/budgie-extras/shuffler/windowrules/net.thunderbird.thunderbird.windowrule:

Cols=1
Rows=1
XPosition=0
YPosition=0
XSpan=1
YSpan=1
Monitor=DisplayPort-2
TargetWorkspace=1