Custom.ts Trouble

On the beta editor,, I’m creating custom blocks and am having a bit of trouble.
On the live lesson,, it shows that you just press the + button and a custom.ts file is added. However, in the editor it tells me to name my file. I tried naming it custom.ts and no code appeared inside it like in the video. (7:04)

Oh, nevermind.
I was in a JavaScript-only editor so of course it didn’t work! :smiley: