-
This’d probably be quite good for that.
https://www.toolstation.com/red-devil-onetime-ready-mixed-filler/p88654
-
That lightweight filler is loved by electricians because you can use it in small quantities straight from the pot and it has a good consistency for quickly fixing problems around sockets and downlighters. It sticks well and has low shrinkage.
If you use it in larger quantities be careful about skin contact and in some cases eye irritation.
Sound! Will pass on the info.