What 1. free 2. offline software for 3. Windows 10 converts math in PDFs To MathJax?
I need software to convert math in lengthy PDFs to MathJax, in order to copy and paste the MathJax to websites like math.stackexchange.com and math.codidact.com. Recommendations must

be unqualifiedly free. Don't recommend Mathpix because it's not completely free.

unreservedly work offline. After I download and install it, it mustn't require any Internet connection to work.

work for Windows 10.
1 answer
This is not a direct answer, but you can just copy the pixels. Scale the PDF so that the equation you want is nicely readable on your screen at a size appropriate for the Math site. Do a screen capture (usually something like ShiftPrintScreen), paste into some image editing software (Paint might work), crop to the equation, export to a new image file, then insert that image file into your post on the Math site.
I follow this process routinely to post snippets of datasheets over on the EE site. It's more complicated to explain than it actually takes to do it. For example, there are three such PDF snippets in my answer here.
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