thanks, you might be curious to review the situation: https://github.com/code-charity/ultimate-REGEX-extension/issues/4 (- if you like the design/vision you can give it 5 stars already rather than being its negative fate for long to come. )
this bug seems a bit familiar from testing an old version, however i didnt write the code and this version works great in Chrome. - Documenting it: https://github.com/code-charity/ultimate-REGEX-extension/issues/5
- probably you could even fix it quickly & feel great about that.