I live in Germany and use both. None do that and as I'm "the IT guy" for many people at work an din private, I'd have heard about it. Hell, the whole continent would have heard about it as whatsapp is widely used.
My Signal also doesn't do that.
I don't even remember how the previous cliënt did it but my spelling suggestions are in English (as is the OS) but my chats are all in Dutch. Most words have a red underline.
It recently gave up downloading images. Turned out it was no longer allowed to write to its own folder. Not sure if this should be blamed on MS but from the (many) user perspective it just stopped working.
It keeps limited chat history which makes it inferior to IRC.
It badly wants you to use ai.
It has a spam channel where it promotes it self.
The phone app is decent tho
I use whatsapp web every day at work. The page. In my Firefox browser. It's almost constantly open. Never had any issues with that. The phone app just does what it's supposed to do and even on my Pixel6, it's just fast. I mean there is always faster but it's not even a second.
I use Whatsapp only because I have to. Privately, I prefer Signal. Works also great. Same with the windows app. Been using both since day 1. On a Pixel7Pro....
Also, what does "fast" mean? Fast on start?
There once was this thread on a blog for a windows XP pirated edition. Someone commented that something small didn't work. They replied in less than a minute, that's terrible! 10 minutes later the version was incremented and a new reply said: Try the new version! After 30 minutes the bug fix was confirmed.
They weren't trying to be funny but it still makes me laugh how it compares to Microsoft, the 3 trillion software company.
Both WhatsUp & Telegram are completely free to use.
Telegram has premium features, but they are tangential to chatting & average use.