YT @Handle URLs to IDs

About
This is a simple program for Windows that lets you bulk convert youtube channel @handle urls to channel IDs/urls.

Youtube handles can change which results in your bookmarks becoming dead links. Channel ID urls persist through @handle changes, which is good for long-term following of channels you're interested in. If you bookmark a Youtube channel, make sure it is the ID, not the @handle.

If you have a lot of youtube @handle channels bookmarked, open up your browser's bookmark manager (CTRL-SHIFT-O) to the folder they are in, copy/paste the @handle urls all into this program, then copy/paste the new ID urls back in.

This program was created because I couldn't find any existing GUI for bulk conversion of @handle channel url into the channel id urls, and it worked for my purposes. Hopefully you might find it useful.

Input:
https://www.youtube.com/@futagoyama-sumofood
https://www.youtube.com/@futagoyama-sumofood/
https://www.youtube.com/@futagoyama-sumofood/shorts
https://www.youtube.com/@futagoyama-sumofood/featured
www.youtube.com/@futagoyama-sumofood/
youtube.com/@futagoyama-sumofood
and so on

Output:
Option 1 - Full Channel ID URLs
Option 2 - Channel IDs only

Note:
Input can be messy text, does not need to be organized pretty into 1 single channel per line.