Hello,
Thanks for contacting us and sorry for any inconvenience that might have been caused due to that.
This is a known bug that happens only in Firefox. If you use Chrome then you will not face this issue. However, even in Firefox, the popup shows that your save has failed but the changes made to the page will be saved.
We are already working on resolving the issue and will soon release a fix for thix. You can keep an eye on our changelog to get notified about the latest updates and features: https://rankmath.com/changelog/
Hope this helps. Let us know if you need any other assistance.
Hello,
Glad that we were able to address your concern.
Please feel free to reach out to us again in case you need any other assistance.
We are here to help.
Thank you.