Mitigates #285452 and we should do this regardless.

cc @deepak1556

To repro:

1. Open devtools console
2. Create 10 terminals
3. Run ls in each of them (or some command that fills the viewport to show sticky scroll), 🐛 a webgl context error occurs in the console
4. Switch between all terminals, the character width should all remain the same (ie. all terminals are using webgl character dimensions, not dom).