Don't delete bad equations, color them red and ignore them

[Divide-By-0]

Also have more robust error handling so that the rest of the equations in the doc properly render. Right now, rendering just stops entirely.

Feedback:

Hi,

Thanks a LOT for your addon. I can draft my thesis in google docs and this really helps me against procrastination since Google Docs is so accessible.

Here is a minor issue: when an equation is incorrect, eg $$\left$$, I get an error message in the addon and the equation gets deleted. This is quite annoying if it took me a long time to write. Also I can be at another place in the document and not notice it being deleted. It would be much better to color it in red instead of deleting it.

Best, Louis...

[grimsteel]

Doesn't this already happen?

Before rendering:

After rendering:

Derendering the bad equation works as expected