PDF Export changing the original document for apparently no reason

So I am trying to find an explanation as to why this is happening. I noticed that there is even a bug report about this from months ago, which received no attention at all — 164240 – Exported PDF doesn't take "Spacing to Borders" into account properly

Misaligned_plus_test.odg (10.8 KB)

As you can see, after you export the document as pdf, the plus sign goes off center for some reason. I tried to check every setting and I still cannot understand why this is happening.

Perhaps because they are not centered.
Select those drawings and, using the alignment tool, center them.

Nope, they are centered. I re-tested it.
Even if they weren’t, why should the pdf file move them anyway.

Maybe I am missing something obvious here. I hope someone figures this out.