edit: to be clear, this is what Slack brings to the table.
In my case, it's suboptimal. There's a multi-second delay between when I type and when the characters show up on the screen. If I were able to use an OS specific client that didn't have these performance issues, then it would be a far better experience.
However, it seems better in their "native" electron client. Still no excuse, performance is terrible in the web client, in my experience, and I'd prefer to use that if I could.
5 frames / 160ms for the key to appear at the start of a chat line.
3 frames / 100ms for the next key to appear
Firefox in a plain text box takes 2 frames / 65ms
What OS you using? I haven't noticed an issue on the rare occasions I use my (7 year old) mac
Slack desktop application best case: 325ms with spell check disabled.
Telegram desktop application worst case: 25ms with spell check enabled
I am sure I wasn't precise in my key press detection. Nonetheless it's still a really sad difference.