- "Error: Find string is blank",
"\ at end of pattern",
"missing terminator ] for character class"
"Warning: Search string ends in white space".
When using Perl pattern matching with UTF-8 support ticked, a known problem can occur when you also have the Case sensitive replace option ticked. This is because the whole topic of character case is not generally applicable for a wide range of Unicode characters.
I therefore suggest that the UI for the Replace filter be enhanced to include the message,
"Warning: Case sensitive replace may give unexpected results for UTF-8 patterns",
i.e. when both the above conditions are met.