That would be fantastic! I have a number of htaccess changes I make to speed websites up on my server. Would be great if I could do them from MainWP.
Forgive me if I misunderstand, but htaccess is not something that can be manipulated via code snippets but actually has to be affected in the file its self. This extension request doesn’t seem plausible. It would require an entirely different approach as it would not be injecting code to head or footer, but some sort of WP hook i imagine. This probably won’t be taken into consideration due to this complexity.
I think you did misunderstood It has nothing to do with injecting code into a theme but adding lines of code/text to an existing file like we can do now within wp-config.php but in this case we could do the same with .htaccess. I’m all for it.