Not sure what you want a screen shot of … so …
I edited the 1st post and added a screenshot of what SketchUp Free
looks like with Dark Reader ON, and no tweaks applied.
When you install Dark Reader it adds an icon to the toolbar to access the Dark Reader menu …
The menu has two pages (currently but the author is overhauling the interface,) …
The 1st page has 3 tabs: Filter, Font, and Site list (which can be used as either an inclusion or exclusion list.)
This is what the 1st page looks like …
The 2nd page is the “developer tools” page, which just displays the Dark Reader extension’s "fix_inversion.json" file, so you can test tweaks “on the fly”. What I do is open Notepad and have the site section in the Notepad editor, and make tweaks there, then copy and paste the whole section to the appropriate (alphabetical) place in the json file, by highlight and paste-replace, displayed on page 2 …
The “Apply” button on this 2nd page makes the local tweaks active.
(But these tweaks can get reset every 15 mins as noted above, requiring this button to be reclicked.)
When the tweaks are finalized a Pull Request is done against Dark Reader’s GitHub master repo, and the author will review make changes if needed and merge the request. (Then users everywhere will get the updated config within 15 minutes. He has already accepted and merged my initial pull request for ruby.sketchup.com and rubydoc.info sites section.)
The “Read about this tool here” link is the one I posted above …
NOW, … I posted a copy of the json (above) section for SketchUp Free in Dark Reader’s GitHub issues to ask for the author’s critique and advice. (… no response yet.)