There are a plethora of SO questions a decade old describing cross platform desktop Regex tools. It seems the most popular options were:
Kodos (no commits in the past decade, runs off deprecated Qt3)
Regexr (desktop version ran on Adobe Air, no longer available)
RegExBuddy ($40, maybe it's the only option)
With Perl 5.10 use
debugcolor(no clue what this even means)
Are there any modern simple regular expression tools that are cross platform (especially Linux) and will run offline on my desktop?