1. Type a very long prompt, such that it wraps to multiple lines
2. Try using the Start/End keys.
3. It moves the cursor to the very start/end of the entire prompt, rather than the start/end of the current line (which is standard/expected behavior - i.e. you can try it in ClaudeCode, or here in Github's textboxes).

This makes it very cumbersome to navigate around long prompts - i.e. it seems like the only way to get from one far edge of the input box to the other is to just hold the arrow key and wait for the key repeat.

If there's an alternative keybinding to do what Home/End typically does, I couldn't find it in https://opencode.ai/docs/keybinds.