I agree there is room for improvement.
Chat rooms tend to be about quick actions, so it should be simple just to see the full message quickly and easily within the chat room.
The current options are not really quick, and take you to a new tab/page and show either message history, or full transcript for a room.
Neither is ideal just to show a truncated starred message.
Alternative idea
The hover over info idea is fine, but there is still a slight delay waiting for it to appear.
What about showing the rest of a truncated message by clicking on it, and the full message is displayed by creating space downover, and pushing any messages below it down a bit.
And it could return to being truncated (e.g.):
- 10 seconds after clicking
- Clicking same starred message again
- Clicking another starred message moves previously clicked one up,
then drops newly clicked message down
Similar to an accordion style setup: JS/jQuery.
Not that design - the current chat room design and layout should remain, that example is just to show how clicking would move messages up/down to create space and show a full message.