Conference: cannot maximise self

Scenario

• Trying to maximize itself when in a conference (but moderator) doesn't work, however maximizing other people is ok.

Problem

• No active participant sent. Only "layout: 0" is sent (corresponding to grid view)

added good-first-issue bug UI/UX labels

added SprintTo review label

mentioned in commit 939f6c20

mentioned in issue #1430 (closed)

added SprintDone label and removed SprintTo review label

closed