Maybe porter rests on this, worker Rex covering (4,3)
I believe the answer is:
beer mat
'maybe porter rests' is the definition.
I don't know anything about this answer so I cannot tell whether this works.
'on this worker rex covering' is the wordplay.
'on' is a charade indicator (letters next to each other).
'this worker' becomes 'bee' (a worker bee).
'rex' becomes 'R' (abbreviation e.g. GR=George Rex, King George).
'covering' becomes 'mat' (mat is a kind of covering).
'bee' next to 'r' is 'beer'.
'beer'+'mat'='BEER-MAT'
Can you help me to learn more?
(Another definition for beer mat that I've seen is " something under a pint?".)