Add new post function has significant problems in Chrome, Edge… not Firefox

[ Moved to the Fixing WordPress sub-forum. ]

For some time now, I’ve been having a very strange issue when creating (and editing) posts inside of Chrome or Edge browsers, but not Firefox. My issue begins when adding a new post–the title and some other data (publish date, etc.)–are auto-populated from an old post. (It’s the same old post, every time.) Saving into draft and going back to edit doesn’t change a thing–the title and all other information are almost immediately repopulated from the old post.) This issue does not occur in Firefox. It’s also not an issue with my system. I’ve done a full re-imaging of my OS, and replicated the issue on more than one device. Because of this, I’m also 99% certain it’s not a DB corruption.

Note: The issue also occurs when editing any posts–it’s like a ghost in Chrome and Edge don’t want to let go of that one post. Anyone else having this same issue?