There is a manager (not my manager) who sits across from me and since we both have open cubicles I can easily see (if I turn) and hear what he is doing. Perhaps I should phrase it differently, it is difficult to not hear what he is talking about. At any rate, he has small meetings at his desk a semi-frequently which I
get the privilege of have no choice in listening to. A few time I have overheard them talking about something I have a very good understanding of (such as our current migration to Git) which they are confused about and I just turned around in my chair and provided my input. It has been a kind of instinctual thing and they seem appreciative, but it occurs to me that this might be rude and intrusive. As I mentioned, I don't really have a choice in listening to these meetings, they are 2 feet from my desk and are not easily ignored. The manager and I are on good terms, if we weren't I would not be doing this.
So am I being impolite or helpful by interjecting in these meetings? What is best course of action? I really have no idea what the best option is here, I get the feeling I should bite my tongue and keep silent, but I feel bad by wasting other peoples time by not helping.
Additionally I can't move away from the meeting, I have a desktop computer and I am a software dev. I could ask him to hold his meetings in an actual meeting room, it would disturb me a lot less, but that seems unlikely to work since we don't have computers in most of the meeting rooms.
Ps. I know listening into meetings is bad to do, I'm not trying to (I'm also not asking if it is bad)... Additionally there is nothing sensitive covered in these meetings, he would find an actual meeting room for that.