Please consider adding a FAQ page to your website and a link to it in Brave for the element blocking feature in Brave adblock. Maybe I’m slow on the uptake, but I finally discovered the most direct way to block elements when the “Block element via selector” window returns an empty result, i.e. fails to populate.
I learned when I receive the empty result (as above), that the easiest solution is to:
Right-click and select “Inspect” on the offending element >
Developer tools simultaneously opens and >
Hover over offending element >
See resulting code of offending element in developer tools window >
Right-click on said code and select “Copy selector” >
Right-click on Brave icon and > select “Block element via selector” >
Paste text to “Block element via selector” > Select OK. >
Voila! Offending element vanishes like magic! 
Now I learned this through trial and error, in addition to posting here on the community. I am an above-average user (not a geek), but the average user would have no clue how to fix empty placeholders or offending cookie pop-ups that slip through Brave adblock. I couldn’t find any info on your website and had to resort to the forum.
The above explanation should be sufficient reason to add clear information on a Help and/or FAQ page. I’m certain that Brave wants more users of its browser so following this suggestion would make it easier for average users to move to Brave and make use of its various features. 
