So I've been taking a deeper look into the issue with '\DifferentialD' and I think the issue is that the MathML specification says we should be using the ⅆ entity but the rest of the world (it seems

) says that really we should be using 'upright d'. I'm using the MathJax mod to render the math notation and the issue with 'DifferentialD' has been discussed there too (see

https://github.com/mathjax/MathJax/issues/1237 [nofollow])

For example, in LaTeX an anti-derivative would, usually, be something like:

`\int x^4 \mathrm{dx}`

... although there doesn't seem to be an agreement on this.

Internally the fMath editor is using MathML so the move away from the DifferentialD entity to '\mathrm' markup was looking tricky

so I replaced it with the letter 'd'

I'll send an email to Ionel (the fMath editor's author) later to see what he thinks about all of this. I guess the other alternative is to filter the LaTeX returned by the editor but that just seemed a little bit clunky.

Anyway, I've updated the plugin on the Your Maths Tutor website. There are a couple more configuration improvements I'd like to make and then I'll try submitting it to the mod site.

Thanks again guys for your help