I'm getting an EXTREMELY specific, odd bug and I don't have any idea what the cause could be.
Playing Pokemon Crystal Clear on Retroarch nightly builds (through title redirect) will cause a crash whenever the Pokedex closes (on the white screen transition), but ONLY if shaders are enabled. Which shader doesn't seem to matter, although some shaders will crash Retroarch immediately when they're enabled. FTR I'm using either the Game Boy LCD shaders or the handheld border shaders on the libretro forums - not sure if those specifically are the problem.
These crashes do not happen on PC with the same shaders enabled, only on Switch. If shaders are DISABLED, no crash occurs, so it's specific to Retroarch on Switch AND the use of shaders. It's also a new issue. I've been able to use the Pokedex with identical shaders in the past without problems.
Unrelatedly (I assume), I've experienced crashes playing Banjo-Kazooie using the N64 core? That's also with shaders enabled. I have so far not experienced crashes playing Earthbound on the SNES9X core, again with shaders enabled.