Only load the plg_content_pagebreak and plg_content_vote languages files when they are needed.
Example: don't load them if the show_vote is not active or there is no pagebreak class.
Enable plugin content vote and plugin content pagebreak
Enable debug and debug lang in global config
Enable debug system plugin with all options activated
Go to frontend and check the debug console
Notice JROOT/administrator/language/en-GB/en-GB.plg_content_vote.ini and JROOT/administrator/language/en-GB/en-GB.plg_content_pagebreak.ini language file is loaded no matter what page you are (even in backend pages they are loaded).
Test patch
Apply patch
Repeat the steps above and checkthe two language files are NOT loaded (except when needed).
Check plugin work as before if language files are required to load (ex: show_vote enabled / article with pagebreak, etc).
@mbabker i updated this PR to follow the logic you added for modules in #11698, but this time for the plugins.
Can you check if all ok?