Steps to replicate the issue (include links if applicable):

• I just edited the page with "edit source" button
• I edited, saw the preview, go back in the browser history, edit again, saw the preview again, go back to edit,... till save the edit

What happens?:

I saved the edit, I didn't receive an edit conflict notification, and the edit erased the two revisions before.

What should have happened instead?:
I should have received an edit conflict notification

Software version (skip for WMF-hosted wikis like Wikipedia):

Other information (browser name/version, screenshots, etc.):

Firefox 113.0.2