Unsafe Flashing theme

[goombapatrol]

This was brought up but never addressed, from what I can tell.
I originally posted in ThirdTube repo's issues without realizing there was a newer fork, so here we go again:

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Hey, I'd like to request you to please reconsider removing the "Flash" option.

I was trying out your program for the first time today and accidentally pressed it when i was scrolling through settings. (I was expecting a "Light / Dark / Follow system time"). After getting full on strobed, I tried to turn it off but it ended up triggering a bad seizure and i went unconscious. (I'm photosensitive epileptic). Somebody else had to turn it off for me.

It's a big safety issue, a dangerous "easter egg" in an otherwise quality program. I don't want this to happen to anybody else.

If you absolutely must keep this in your program for some reason, make a popup warning or something so you have to confirm enabling it.

Thanks for making an otherwise nice program.