I have written in a previous job messages, but it usually went like this:
Hello, [Name]! Hope you’re not too busy! I have questions regarding [whatever the fuck it was on about]
Mostly because I hate getting a message and it is just a wall of text, the greeting allows for a slight breathing room and a chance to spot a typo.
But I never left the other hanging, more than a minute to type the needed thing up. If it was taking longer, I would just send it in chunks.
That’s fine. To each their own.