Google Search Console - Strange Crawl Error

Questions
1

On my Google Search Console, I was recently notified that there is a lot of 404 errors:

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However, the results are listing pages that never existed in the first place. I’m trying to narrow down why this is the case. Would any of these be Bubble-related?

2

I’ve seen a few other cases of this happening on the forum. @romanmg was this something you encountered?

3

Yes, here: Dozens of 404 Errors

While it eventually stopped for me, the cause is still a mystery.