how to make github copilot to understand Svelte5 llms?

VSCode user here, I want to pass below file to copilot

https://svelte.dev/llms-full.txt

I created .github/copilot-instructions.md , and it seems it does not read external link, so I downloaded llms-full.txt , but in the chat window, it still requires me to copy paste the content, which will not work because the file is huge.

Anyone has figured out how to make copilot more aware of svelte5?