Caps Lock detector


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This script


Detects if Caps Lock is engaged when a key is pressed in a text input.

Current version

Appears to be 2.0.0

Browser support

Trident / EdgeHTML / Tasman (Internet Explorer 4+, Edge 44-)Works in all except IE 4.x on Windows (it thinks 'A' and 'a' are equivalent)
Opera 7-12Script works as expected
Gecko engine browsers (Mozilla, Firefox, Netscape 6+, etc)Script works as expected
KHTML / WebKit / Chromium / Blink / QT WebEngine / QTWebKit / WebKitGTK (Chrome, Vivaldi, Opera 15+, Edge 79+, Safari, Konqueror, OmniWeb 4.5+, iCab 4+, NetFront Chromium / WebKit)Works in text boxes with Safari and OmniWeb 4.5 (they have their own warnings for password boxes) - partially works in Konqueror 3.2+ (it gets it wrong if they press the Shift key) - does not work in Konqueror 3.1- (it thinks 'A' and 'a' are equivalent)
iCab 3-Script works as expected
Rhino + W3C DOM (ICEbrowser)Script works as expected
Rhino + layers / W3C DOM (Escape / Evo, iBrow)Browser thinks 'A' and 'a' are equivalent
NetFront 3+ NetFront engineScript works as expected
Opera 5 and 6 Elektra engineScript works as expected
Netscape 4Script works as expected
OmniWeb 4.2-Browser thinks 'A' and 'a' are equivalent
Rhino + pDOM (Clue browser)Browser thinks 'A' and 'a' are equivalent
WebTVBrowser thinks 'A' and 'a' are equivalent
Tkhtml Hv3+Browser cannot detect key events
Netgem NetBoxNot tested but it should work
OpenTVNot tested but it should work
iPanel MicroBrowserNot tested but it should work

Accessibility notes

No accessibility problems. Caps Lock cannot be detected if JavaScript is disabled.


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