For what it’s worth, this is coming from a guy that used to be kenc@microsoft.com (1988-97) – “Ken C-is-for-Chart”, they called me (an area I was responsible for in Works and just a bit in Excel) – Microsoft, where half the folks I worked with were, like the agent today, from India! And it has occurred to me, as I have observed the program behavior detailed in the accompanying doc file, that hey, if I were the programmer on the other end of the program – Acrobat, in this case – I would want to know about this behavior!

Given that this web page offers file uploading, I guess the only (only??) roadblock possibly remaining is whether it will allow uploading this unique file, at all of 175Mb!...?

Since I am submitting this “idea” – to be considered a bug, presumably, since clearly Acrobat is not behaving the way anyone would like it to! – submitting while signed in on UserVoice, one would hope that if the big file doesn’t “go”, sign-in info will be available to Adobe? such that you can contact me, hopefully with another way to get you the file? …as I said, in some way it is “unique” in causing this, ahem, untoward behavior.

So here goes, uploading the details in “Save problem description.docx”, and trying to upload “Chinese-English Dictionary (Giles, 1892, 1912).pdf”.

Well... the big file it seems didn't "go", but also without any rejection notice or report of failure. 

By the way, lastly – if it turns out that someone is interested in this! – that file contains no personal information, only highlighting and bookmarking of various dictionary entries.  And the file (1912, scanned and somehow OCRd, including the Chinese, in the original) originally came from archive.org at https://archive.org/details/b31352583/page/552/mode/2up (just verified).

Yeah, one more thing, without re-editing the attached file:  That file mentions the versions of Acrobat involved, but does not mention that my machine is running Windows 10, my wife's Windows 11, with the same "bizarre" behavior.  :-)