Seems to work, but not fully.
I was a bit irritated by the inability to scroll the installation instructions (they don’t fit on the entire iPhone SE screen) and that the Settings page does not load, but I can change website fonts as needed. Additionally, it handles the Regular, Italic, Bold and Bold-Italic files of one font as four separate fonts. This must be fixed, as it totally breaks bold and mostly breaks italic. Even converting them to a .ttc collection does not fix this, it just uses the first font from it and uses faux oblique and almost-invisible artificial emboldening.