Is it mustahabb for one who gets up to leave a gathering to say salaam to those who are still sitting?

No File Exists
Check below answers in case you are looking for other related questions:
Is it correct to end a letter with the phrase “wa’l-salaam”?
Is it bid’ah for a person who is already there to say salaam to one who has just arrived?

No File Exists
Related Answers:
Shaking hands with women in Ramadaan
Is it valid to greet people by saying salaamun ‘alaykum?
Martial arts greeting by striking the palm with the fist of the other hand
Is it correct to end a letter with the phrase “wa’l-salaam”?
Is it bid’ah for a person who is already there to say salaam to one who has just arrived?

Recommended answers for you:
Celebrating the night of the Isra’ and Mi’raaj
The etiquette of eating, with detailed evidence
Khula’: definition and how it is done
Woman’s ‘awrah in front of other women and mahrams
Seriousness of debt