Upgrade Insecure Requests
- CRDeclare that browsers should transparently upgrade HTTP resources on a website to HTTPS.
IE
- 5.5 - 10: Not supported
- 11: Not supported
Edge
- 12 - 16: Not supported
- 17 - 86: Supported
- 87: Supported
Firefox
- 2 - 41: Not supported
- 42 - 83: Supported
- 84: Supported
- 85 - 86: Supported
Chrome
- 4 - 42: Not supported
- 43 - 86: Supported
- 87: Supported
- 88 - 90: Supported
Safari
- 3.1 - 10: Not supported
- 10.1 - 13.1: Supported
- 14: Supported
- TP: Supported
Opera
- 9 - 29: Not supported
- 30 - 71: Supported
- 72: Supported
iOS Safari
- 3.2 - 10.2: Not supported
- 10.3 - 13.7: Supported
- 14: Supported
Opera Mini
- all: Not supported
Android Browser
- 2.1 - 4.4.4: Not supported
- 81: Supported
Opera Mobile
- 10 - 12.1: Not supported
- 59: Supported
Chrome for Android
- 87: Supported
Firefox for Android
- 83: Supported
UC Browser for Android
- 12.12: Not supported
Samsung Internet
- 4 - 12.0: Supported
- 13.0: Supported
QQ Browser
- 10.4: Supported
Baidu Browser
- 7.12: Supported
KaiOS Browser
- 2.5: 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">
.