RegexKit is a Chrome add-on developed by cherrimonshop. It is a free tool designed to assist developers in searching and testing regular expressions. With RegexKit, users can easily search for regular expressions with affix. The add-on works by searching the entire HTML and highlighting any matches it finds. It also provides the ability to capture groups within the search results. The captured groups, along with the search results, are then sent to the popup for further analysis and evaluation.

RegexKit is a valuable tool for developers who frequently work with regular expressions. Its simplicity and ease of use make it a great choice for those looking to efficiently search and test their regular expressions. With the ability to search the entire HTML and capture groups, developers can quickly identify and troubleshoot any issues with their regular expressions. RegexKit is a must-have add-on for any developer's toolkit.