Detecting NPAPI support in Chrome using javascript
Had an issue created by chrome 42's disabling of NPAPI. What was done was something in the lines of this: (similar to )
function isJavaAvailable() { var javaRegex = /(Java)(\(TM\)| Deployment)/, plugins = navigator.plugins; if (navigator && plugins) { for (plugin in plugins){ if(plugins.hasOwnProperty(plugin) && javaRegex.exec(plugins[plugin].name)) { return true; } } } return false;}var chromeVersion = window.navigator.userAgent.match(/Chrome\/(\d+)\./);if (chromeVersion && chromeVersion[1]) { if (parseInt(chromeVersion[1], 10) >= 42 && !isJavaAvailable()) { // do chrome-no-java-related task console.log('Java not available'); }}This is not a direct "NPAPI-detector", but can be rewritten to test for the plugins affected by NPAPI disabling through changing the regex for instance. Regex was used for some kind of robustness. Had a look into navigator.plugins['some-number'].names to find what to check for.
Due to auto-updates, Chrome users are generally running the latest version; once that rolls out, you should probably just assume that Chrome users don't have NPAPI support, and serve them the alternate content.
There is no javascript api to check NPAPI support, but as workaround I can suggest you to check browser version of Chrome.
If Chrome version older then 42 than NPAPI support is disabled. Yes, from 42 and before 45 version you can use chrome://flags/#enable-npapi but there is no way to check this flags from JS
For now I guess it's pretty actual information:https://www.chromium.org/developers/npapi-deprecation?pli=1