I saw this and wondered should I worry?

[SimonM]

What it may be , a bit of damp on top of the dust on the barrel. It’s not losing gas.

 

[Pudsey Bear]

Odd. What's above the gas locker?

 

[SimonM]

Nothing of any concern. I reckon this out of the tap area

 

[mistericeman]

Could just be "sweating" in the warm humid weather we've been having if you've been using gas....
I'd spray some leak detector on it just to be sure
(I keep a can in the gas locker just so I can give any joints a quick spray periodically)

 

[Pudsey Bear]

I never travel without leaks spray, WD40 and silicone lube, never know what a bear will need

 

[SimonM]

I wiped it all off first thing this morning, I looked at it earlier and there’s no repeat yet