Fix TextEdit's character limit #6542

Job	Run time
Check wasm32 + wasm-bindgen	10m 34s
android	3m 11s
cargo-deny aarch64-apple-darwin	1m 59s
cargo-deny aarch64-linux-android	1m 47s
cargo-deny i686-pc-windows-gnu	1m 46s
cargo-deny i686-pc-windows-msvc	2m 7s
cargo-deny i686-unknown-linux-gnu	1m 59s
cargo-deny wasm32-unknown-unknown	2m 17s
cargo-deny x86_64-apple-darwin	1m 54s
cargo-deny x86_64-pc-windows-gnu	2m 5s
cargo-deny x86_64-pc-windows-msvc	2m 2s
cargo-deny x86_64-unknown-linux-gnu	2m 9s
cargo-deny x86_64-unknown-linux-musl	2m 4s
cargo-deny x86_64-unknown-redox	2m 12s
Check Windows	10m 52s
Format + check + test	32m 48s
	1h 21m 46s

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