letters in epub to pdf conversion on top of one another

[Brian Prager]

Calibre 5.6
Windows 10

I've used Calibre to convert thousands of books from epub to pdf, successfully and perfectly. (I use this for myself and for teaching university classes. The idea is to imitate the appearance of books or published papers in the pdf, with margins etc, rather than the marginless, spacesless format of ebooks.)
Sudden new behavior, letters are now produced superimposed on one another in the pdf output. Never happened before.
Difficult to describe. The letter d will be moved to the left one space, so that the word "moved" is turned into "mov ed" with the "e" and the "d" occupying the same space in the type, one on top of the other.

Problem with the bug reporting guidelines below! I would be glad to attach both the input and output file, but the interface here only allows me to make a single attachment. So I am uploading the output (pdf) file. The input (epub) looks normal to me when I open it using the ebook reader in Calibre. But as might be apparent, I am no software developer and can't determine if there is a structural problem with the original that is producing the bad pdf output file.
THanks for your help. I hope you're able to recognize a familiar problem and let me/ us know.
Gratitude, Bwp123

[Kovid Goyal (kovid)]

See https://github.com/kovidgoyal/calibre/commit/4fb58f192e6da795bb62bab6dae0daad174b5578

You can wait for the next release in about ten days or downgrade to calibre 5.5,
old releases are available from: https://download.calibre-ebook.com/

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