I redownloaded Textra after a mishap, and that ended up removing the custom vibration pattern option (pixel 4a). Now that it is gone, the default vibration pattern is horrible, it's just one long strong buzzzz. The new one is very jump scare inducing and let's everyone else in the room know I got a text. I don't know if it's impossible to add the custom pattern option back, but at the very least, please calm down this default one, it's not good at all