Learning Resources

RegexOne - Learn Regular Expressions - Lesson 1: An Introduction, and the ABCs
RegexOne - Learn regular expressions with simple, interactive exercises.
GitHub - ziishaned/learn-regex: Learn regex the easy way

Filter Bypass

I'd say that mastering regular expressions could be enough to come up with bypasses.
XSS - Bypass this RegExp
Information Security Stack Exchange
Copy link
Learning Resources
Filter Bypass