Depends on D4075
Adding an attachment holders delimiter. Holders are built from:
- hashes - these are hexadecimal values - 0 to 9 and A to F (or lower case)
- uuid - also hexadecimal - 0 to 9 and A to F (or lower case)
- `ID_SEPARATOR` - `:`
So it's impossible to have `;` character that would not be a delimiter.