Topic: Is there any possible risk with covers?

Near launch I remember I heard of some problems that some covers could cause, damaging the Switch and Joy cons plastics, but at the same time I would like to have an ergonomic cover to make it easier to hold it firmly when I use it in handheld mode and to get my hands less tired, but I'm always scared that the cover I choose could damage my console, so I'd like to know once and for all: is this risk real? And if it is, what I need to know to avoid it when I choose a cover?

@LuckyLand
Try HORI.
They are reliable, high quality 3rd party accesories.
Btw, my Switch has NO Clear case to protect its body, but have no scratch at all, except my screen (but thanks to Tempered glass screen to protect from the scratch)

I don't need to protect it, I just want something that makes it more bold and shaped to make it easier and more comfortable to play it in handheld.
Something that can be put in and out as often as I want since I should remove it everytime I don't use it or use it docked
Thanks for the advice I'll take a look to what Hori sell

IIRC it was the self adhesive stickers that were damaging the Switch and joy-con casings. I don't think covers (silicon skins) were involved, although I may have missed that report.