Exported PDF doesn't render mathjax

[justineuro]

This is related to #138.
ReText v7.0.4 installed in Windows 10 inside Anaconda environment (i.e., it was installed with python -m pip install retext issued in an Anaconda terminal). MathJax is installed in C:\MathJax.
When retext is issued in the Anaconda terminal, the math formulas are rendered under the Preview mode but not when exported as PDF. A screenshot showing the preview mode and the corresponding exported PDF file are attached.

The Print Preview also does not render the math.

PDF file:
ex001.pdf

[mitya57]

This was happening because printing and PDF export was not implemented for the Qt WebEngine backend, so it was falling back to QTextEdit backend.

I have now implemented PDF export for QtWebEngine, please try the latest commit in master.

There is no print support yet (and print preview is also not working), but you can export to PDF and then print it.