Math in titles seems not to be rendered now on the main page.
I've tried clearing the cache in Firefox. Also discovered that a "hard refresh" in Firefox for Linux is a CTRL-F5, and it also does not fix the rendering problem.
It appears the "active" button is causing the cropping in the thread titles, as in both Meta and the parent site, the titles are cropped just before the column that the active button sits in.
2nd edit: at the bottom of the page under the list of thread titles there's a horizontal slider bar. So I can scroll to the bottom of the page and use the slider to read the other half of the thread titles. Seems rather inefficient.