Upgrade Insecure Requests
- CRDeclare that browsers should transparently upgrade HTTP resources on a website to HTTPS.
Chrome
- 4 - 42: Not supported
- 43 - 116: Supported
- 117: Supported
- 118 - 120: Supported
Edge
- 12 - 16: Not supported
- 17 - 116: Supported
- 117: Supported
Safari
- 3.1 - 10: Not supported
- 10.1 - 16.6: Supported
- 17.0: Supported
- 17.1 - TP: Supported
Firefox
- 2 - 41: Not supported
- 42 - 116: Supported
- 117: Supported
- 118 - 120: Supported
Opera
- 9 - 29: Not supported
- 30 - 101: Supported
- 102: Supported
IE
- 5.5 - 10: Not supported
- 11: Not supported
Chrome for Android
- 117: Supported
Safari on iOS
- 3.2 - 10.2: Not supported
- 10.3 - 16.6: Supported
- 17.0: Supported
- 17.1: Supported
Samsung Internet
- 4 - 21: Supported
- 22: Supported
Opera Mini
- all: Not supported
Opera Mobile
- 10 - 12.1: Not supported
- 73: Supported
UC Browser for Android
- 15.5: Supported
Android Browser
- 2.1 - 4.4.4: Not supported
- 117: Supported
Firefox for Android
- 117: Supported
QQ Browser
- 13.1: Supported
Baidu Browser
- 13.18: Supported
KaiOS Browser
- 2.5: Supported
- 3: Supported
The HTTP header is Content-Security-Policy: upgrade-insecure-requests
. Alternatively, the HTML tag is <meta http-equiv="Content-Security-Policy" content="upgrade-insecure-requests">
.