Is it this?
To reproduce:
1. I used the default Windows IME, not third-party. Language Chinese Simplified. On Windows 11.
2. Let the code editor be empty.
3. Type a letter. Appears IME window.
4. Click somewhere in the code editor. The IME window disappears, and LA shows the intellisense list.
5. Double-click an item in the list. Or click and Esc. Use mouse, not keyboard.
6. Undo.
7. Type something to invoke IME again. This time IME window is at the right side of the primary screen, and does not work.
8. To make it work again, focus another control, or activate another window.
BTW, step 5 can also reproduce another your reported bug - exception when inserting a snippet. It happens when the caret is at the very end of text.
To reproduce:
1. I used the default Windows IME, not third-party. Language Chinese Simplified. On Windows 11.
2. Let the code editor be empty.
3. Type a letter. Appears IME window.
4. Click somewhere in the code editor. The IME window disappears, and LA shows the intellisense list.
5. Double-click an item in the list. Or click and Esc. Use mouse, not keyboard.
6. Undo.
7. Type something to invoke IME again. This time IME window is at the right side of the primary screen, and does not work.
8. To make it work again, focus another control, or activate another window.
BTW, step 5 can also reproduce another your reported bug - exception when inserting a snippet. It happens when the caret is at the very end of text.