Gmail Pre-Send Alert

▼Short description
Shows a confirmation dialog before sending in Gmail. Checks recipients, domains and custom rules. Japanese & English supported.

▼Full description
“Gmail Pre-Send Alert” prevents misdirected emails by showing a confirmation dialog before Gmail actually sends. It evaluates recipients against multiple safety rules and asks for confirmation only when needed.

■What it does
Warn if all recipients (TO/CC/BCC) are empty (toggleable)
Confirm when the number of different domains (TO+CC+BCC) ≥ your setting
Confirm when total recipients (TO+CC) ≥ your setting
Confirm on From × To pair rules (regex or exact, add multiple rules)
Works with Ctrl/Cmd + Enter (no hidden/parallel sends)
Japanese / English UI, following the Chrome display language

■How to use
Install the extension
Open Gmail
When sending, a dialog appears if any rule is triggered
Tune thresholds and rules in the Options page

■Recommended defaults
Different domains: 3
Total recipients: 5
Pair rule examples
From: ^[email protected]
$

To : .*@partner.com
Tip: When writing regex in JSON, escape backslashes as “\”.

■Permissions & Privacy
Only “storage” permission (to save your settings)
No collection or transmission of email contents or recipient data
See our Privacy Policy for details

■FAQ
Q. Does it send immediately when I press Send?
A. No. Sending is blocked until you respond to the dialog. It sends only if you press OK.

Q. Could Gmail UI changes break it?
A. If Gmail’s internal selectors change significantly, we will update the extension accordingly.

■Changelog (highlights)

v1.2.0: JA/EN i18n, stability fixes (pre-send race), new Options page

■Keywords
Gmail, pre-send, confirmation, alert, recipients, domains, rules, compliance, productivity