Well it's not really Linux, but it has a Linux version,
and it's not FOSS, but it's free for use in creating FOSS software.
Just figured there might be some around here who would want to know. I had a year's subscription a while back and only came across this news by chance.
https://blog.jetbrains.com/blog/2024/10/24/webstorm-and-rider-are-now-free-for-non-commercial-use/