Steps to reproduce:

1. Create an item
2. Create a trigger
3. Use ‍{{ITEM.VALUE}.regsub(.*, \0)}‍ in both trigger name and tags
4. Make sure that item received a value
5. Go to Monitoring->Problems or Monitoring->Triggers

Result:
Sequence got replaced with item value (since pattern .* matches everything) in tags by server and with \0 by frontend
Expected:
In both cases \0 should be replaced with a matched text.