Adding subs to another person's YT video

Hello, I'm asking if you guys know any stand alone subtitle program I can use for adding subs to yt videos? I've just been using the community subs to add them but they've been recently removed by youtube.

I'm also asking if you guys might the program used for adding subs to this video:
Turn on the eng subs for it so you can see

https://www.youtube.com/watch?v=9tLA...hannel%2Fcover

I recall a certain program I found for adding fansubs once but now I really can't remember the name of it so pls help me out. I want to keep contributing to sub guys :<

This is so sad, YouTube axed community subtitles on September, this means people can't add subtitles unless they are the video's creator. Still, Aegisub is a great tool for subtitling, its open source and free!

The program you're looking for is a freeware and it is call "MKVToolNix" ..and you find it here

https://mkvtoolnix.download/

just choose your operating system and your on your way ...btw they come as an "install" or as "stand-a-Lone" version...I use it in my Fansubbings...

oops ..these make a "softsub" subtitled file..

This will "mux" your subtitle file into your video creating a MKV

You can create the subs using aegisub (Aegisub Advanced Subtitle Editor), save it in .srt format and add it to the youtube video in the settings (if you're the uploader, of course).
You could also send those subs to the original uploader and ask them to add it themselves.