Ok, now this trick is honestly a trashy thing to do....but it has worked twice for me, but it may not confirm, so someone test it out.
If you want to farm an area and someone is gliding in it, and you are PRETTY sure after whispers with no response and such that they are gliding, send them:
[Yano] whispers: Kk I reported you (space here to the end until the cursor skips, then you know that it is on a new line) <GM> [Cake] whispers: Hello
This should appear to them as:
[Yano] whispers: Kk I reported you
<GM> [Cake] whispers: Hello
Now, Glider DC's if it detects a whisper from a GM, as in it shuts down, meaning if they are farming that area while gliding and not watching it, they won't be farming anymore. This has worked twice for me, but COULD be because they were farmers and didn't want to risk being banned. It may be that Glider relies on the ACTUAL GM whisper to DC.
Nonetheless, worth giving a shot. Managed to clear me a spot to farm. Again, a low-down dirty tactic, but hey, what's life without a few laughs.