Home > FAQs > OpenCues on Gmail

Does OpenCues work on Gmail?

Yes, fully. Gmail's compose box is a generic contenteditable surface with no managed editor framework in the way, which makes it the Chrome extension's most reliable target: the full feature set runs there, and it's one of the sites the project verifies against.

What works in Gmail compose

Everything the extension offers: word cues dim and cycle, blanks fill (weather london _, translate to french _, draft an email _), transform rewrites apply (make this more formal _), and the inline agent runs (agentically correct spelling _). Rendering uses the CSS Custom Highlight API, painting inside Gmail's own text rather than overlaying it, so the page layout is never disturbed.

Undo behaves properly

Every OpenCues write into Gmail lands as a single browser-level undo entry (an insertHTML replacement over the selected content). An earlier design produced two entries, so the first Ctrl+Z flashed an empty compose box; that was fixed after user reports in May 2026, and one-entry undo is now a verified invariant. Ctrl+Z after any fill restores exactly what you had.

Even text styling works here

Gmail is one of the few sites where make wilfred bold _ actually renders bold, because with no editor framework intercepting, the browser's native bold command wraps the range directly. Managed editors elsewhere (ProseMirror, Quill) usually refuse programmatic styling; Gmail accepts it. Bold, italic, and strikethrough are attempted; code, heading, and list styles are skipped on Chrome.

Details worth knowing

Identity-context drafting shines here: draft an email to my landlord _ comes back signed with your stored name, and in the default safe mode your personal values never reach the provider.
Sensitive fields are never attached: password, payment, and OTP inputs are refused by a default-deny check, in Gmail and everywhere else.
Gmail quirks are handled: pasted emoji that Gmail converts to inline images are read via their alt text, and a fixed bug class around Gmail's trailing blank-line placeholder no longer piles up empty lines when cycling multi-paragraph rewrites.