Render one frame before showing the window to avoid flashing (#777) #2401

Job	Run time
cargo check (msrv) (wasm32)	25s
cargo clippy (windows-latest)	5m 40s
cargo check (msrv) (windows-latest)	1m 44s
cargo clippy (macos-latest)	2m 9s
cargo check (aarch64-android)	25s
cargo check (msrv) (macos-latest)	37s
cargo clippy (wasm32)	2m 1s
cargo clippy (ubuntu-latest)	3m 29s
cargo check (msrv) (ubuntu-latest)	50s
cargo doc	1m 52s
formatting	29s
Prime LFS Cache	3s
cargo test (wasm32)	20s
typos	5s
cargo test (windows-latest)	2m 44s
cargo test (macos-latest)	1m 33s
cargo test (ubuntu-latest)	3m 56s
	28m 22s

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