The issue was with pdfminer interpreting the Unicode mapping data. If Ghostscript rewrote it, it could have worked around the issue. Even a one byte adjustment could have been a workaround. --redo-ocr ...

Feature request EOL of Python 3.4 and 3.5 are 2019/3 and 2020/9, respectively. How about dropping support of these versions this October so that we can enjoy new features like f-strings?