macOS native keyboard shortcut is overridden
macOS has its native keyboard shortcuts that are helpful for text editing. However, some of them doesn't work on Microsoft Teams.
* Control-A: Move to the beginning of the line or paragraph.
- DOESN'T work. Instead, all texts are selected (the same as Command-A)
* Control-B: Move one character backward.
- DOESN'T work. Instead, selected texts become bold (the same as Command-B)
Control-A is quite important for me because it is the very common shortcut in Linux/Unix environments. Refer "Moving faster" section on this link for the details.
For all native keyboard shortcuts on macOS, please refer the following official document.
Mac keyboard shortcuts - Apple Support