Same problem here. Seems Rank Math is doing something with the .htaccess so it won’t work anymore. Here it happened after activating the “Redirect Attachments” option, the site instant went into an Internal Server Error.
Solution for now: Use the .htaccess backup and make it not writeable anymore via FTP. Otherwise Rank Math will overwrite it again and again and again.
Thanks for your help Thomas I appreciate the offer, but I think I’ve got things figured out now mostly. Initially my .htaccess file was completely missing anything in <>, like </IfModule>. The second time, I couldn’t find a difference with diffchecker, but restoring the backup RM created worked. Weird. For now I’ve made my htaccess file read only. Thanks for that tip.
You’re welcome. Nontheless RankMath need to figure out what’s wrong with overwriting the .htaccess in that completely weird manner. As long as this happens over and over again and the .htaccess is read only, other plugins like WP Fastest Cache might get broken too.
Thanks for getting in touch and sorry for the inconvenience caused.
I am glad that you were able to fix this issue, I cannot reproduce this issue myself but your findings have been submitted to our dev team and we will be digging deeper into this issue and get back to you.
We appreciate your patience and understanding in this.