VLC (git) crashes when displaying text over the video

For a while now, my vlc-git (4.0.0-*) keeps crashing when attempting to display any text overlays over the window, including:

the video title (I usually have to launch it with vlc --no-video-title)
timestamp and duration when jumping around with Ctrl/Shift/Alt + left/right arrow
volume when adjusting it with up/down arrow

The crashes are not always the same: sometimes the signal is SIGSEGV (segmentation fault) and sometimes it’s SIGABRT (abort), and the backtrace differs as well, with the crash sometimes coming from libharfbuzz.so and sometimes from libfreetype_plugin.so. (I guess it’s possible these are separate bugs? Not sure.) I’ve pasted some coredumpctl info vlc output at https://gist.github.com/lucaswerkmeister/2f4b9534b04f951603cda1e29cede4b8.

I’ve attempted to git bisect the bug, and the bad commit seems to be a2b5b533. I’m not quite sure of that – the bug is not quite reliably reproducible, and earlier in the bisect I mismarked some revisions, from which I then tried to recover – but the commit very relevant (“text_renderer: freetype: fix memory leak in AnalyzeParagraph”, fixes #20881 (closed)), so I’m CCing its author and sign-offer (assuming I don’t fail at Trac).

I’m on Arch Linux, with the following software versions:

freetype 2.9.1-1
harfbuzz 1.9.0-1
Linux 4.18.10.arch1-1
glibc 2.28-4

If you have trouble reproducing the bug, I’ll be happy to test any patches you want to send my way.

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