[RKFADU_UOFCCLEL]

I tested in Tor Browser at standard security level and it's blank except the thumbnails on the left show fine, so just a minor glitch somewhere is breaking it. I presume it doesn't support TOC then, which is a shame. On the upside, the signature feature is well appreciated, something sorely missing from most other PDF editors.

[philjohnson]

Sorry about that. Would you mind sharing the console logs? Perhaps it's showing an error that I can use to debug and fix. Thanks!

[RKFADU_UOFCCLEL]

It will be easier for you to run Tor Browser yourself. TB is made to act exactly the same on all platforms.