Rated 2 out of 5 stars

Good work until the limit 2²⁰ to the permissions list (about 20800 sites). List badly reduced, since there is no regular expression or mask.
And the import does not work well with IDN, since there are errors such as encoding Ð»ÐµÐ½Ñ‚Ð¿æƒ a domain site.

This review is for a previous version of the add-on (0.5.30). 

I'm sorry, but RequestPolicy v0.5 Legacy was not designed for large amounts of rules. Please upgrade to “RequestPolicy Continued”, its successor. If you've got problems migrating your rules to RP-Continued, best contact me on Github.

More in detail: RP v0.5 used the Preferences (available via “about:config”) to store the rules. According to Mozilla's developer documentation (i.e. nsIPrefBranch), large amounts of data should be saved in a file. This is what RP-Continued is doing.