Document the IME cursor area workaround #2599

Job	Run time
cargo check (msrv) (wasm32)	17s
cargo check (msrv) (windows-latest)	1m 13s
cargo check (aarch64-android)	20s
cargo check (msrv) (macos-latest)	47s
cargo clippy (windows-latest)	5m 13s
cargo clippy (wasm32)	1m 55s
cargo check (msrv) (ubuntu-latest)	35s
cargo clippy (macos-latest)	2m 13s
cargo doc	46s
cargo clippy (ubuntu-latest)	3m 12s
formatting	2m 43s
Prime LFS Cache	7s
cargo test (wasm32)	18s
typos	7s
cargo test (windows-latest)	3m 17s
cargo test (macos-latest)	2m 47s
cargo test (ubuntu-latest)	3m 51s
	29m 41s

Provide feedback