Any advice on how to stabilise this flake? It is the top hold to a few problems and whilst I don't think it currently moves, it does look and feel pretty insecure. It does look like someone has had a go at fixing it in place previously along with some other holds at the crag. I'm not sure on when this was done but it was definitely over ten years ago and doesn't look the smartest job.
I appreciate the best thing to do would be to prize it off, clean it up and then stick it back on but it is quite large and might be hard work to hold it in place whilst the glue sets.
Would pumping the back of it full of resin work at all?
If it did come off it is of a size and at a height that it could seriously injure someone if it landed on them. It would probably leave behind something useable and wouldn't make the problems any harder but it would leave a less satisfying finishing hold.