RSTA isn't the fastest when faced with very long lines. For example, as originally reported on SourceForge here:
"When the RSyntaxTextArea has one line with many characters (more than 15 000) and has the "Line Wrap" option enabled, using the option "Select All" takes too much time to select all the text. Trying to use the scroll bar with all the text selected also takes too much time. Navigating the text with the arrow keys up and down takes more time than normally would. Editing the text or navigating with the arrow keys left and right takes the normal time."
This ticket is to track performance improvements with WrappedSyntaxView. There is no specific end-goal for this ticket other than "noticeably faster in some instances." No hard metrics.