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Is there a way to detect if MS Visio, MS Word, or any MS Office app is installed on computer from IE & Chrome?

I have a SharePoint 2019 document library wherein I have a custom JavaScript code to open the MS documents (Word, Excel, Ppt, Visio) in the client application. I am using Office URI schemes for opening the documents in client apps. However, if there is no client application installed on the computer, the Office URI scheme fails without throwing up any error. I want to know if there is a way to check from the browser (IE and Chrome) if a particular MS application (Visio, Word, etc.) is installed on the computer.
P.S. I have tried the ActiveXObject approach, but for some reason, it didn't work for me and, also I want a solution that will be cross-browser compatible and afaik ActiveXObject is supported only on IE.

(Current MSFT employee in Office here. On the team that owns the link invocation handling for the native client side but not the SharePoint or JS side)
The root problem is that the browser object model doesn't give you a result for navigating to the ms-word/etc links. As I understand it that is why the built-in SharePoint open UX has 2 options. One to open in the browser and another to open in the native client. And there is interstitial UX to prompt the user if the file did not successfully open in the native client.
(And, correct, the ActiveX solution will not work even with modern Edge on windows either and is a dead-end technology wise.)

You can try using ActiveX technology to instantiate Office application as described on the detect microsoft office version using javascript thread. But Chrome is not aware of COM technology. So, any code for creating an Office application instance will fail.

Google Chrome Custom URI-Scheme redirection to JS

I am currently working on a custom uri-scheme (protocol) in google chrome and require a method to automate some testing (and development) of this protocol purely from within the chrome browser.
For example. If a redirect/anchor link points to this example uri
testuri://thismessage/additionaldata
then I would like to to redirected back into JS somehow. I.e. with a call to say
function protocolMessage(data) { ... }
I have explored the use of 'navigator.registerProtocolHandler' but that requires the use of 'web+testuri', which isn't an option (unless someone knows of a setting that can be used to turn this off).
I have investigated using a chrome custom extension to capture the uri under webNavigation but it doesn't capture anything but http(s) schemes. And I cannot see any functions that would allow me to register a custom scheme directly either.
Further investigation led me to try calling out to a system application (using custom uri-schemes that call native executables) and this partly works but now i'm stuck on how to redirect that message back into the current page/tab's javascript.
I also had a look at NaCL (Pepper API's) but that doesn't seem to allow registration of custom schemes either.
I am hoping for a better solution than calling out and back into the browser, but if not can anyone shed any light on a good solid reusable solution?
Any ideas?
Thanks in Advance

To my knowledge, no, sadly.
All Chrome APIs work with "supported schemes" and you can't add one.
web+custom: is also an inflexible limitation.
If you have a system application, you can talk to it by either providing a WebSocket server in the application, or working with Native Messaging.
The problem with native messaging is that Chrome has to initiate the connection to a new instance of the Native host. So you'll need to be able to handle the native app being invoked separately for protocol handling and for messaging.

How to use the browser as the GUI for an offline application?

I want to be able to create an offline program that can use the browser as GUI. I'm not particularly good at GUI programming in general, and overall it seems that using HTML and CSS to structure a GUI would be the easiest.
Cross browser method is preferred, but I will most likely use Google Chrome
I need to be able to open an external program, possibly with command line arguments
Javascript seems like the best language for this, however as far as I know it isn't possible to launch programs with it.
This is on Windows 7.

That's a good idea and is done by a several popular softwares.
The best way is to make your offline program run a web server that the browser will be able to access.
ie: Your program starts a web server on localhost:5555 and then you'll be able to request http://localhost:5555/users in Javascript, from your browser.

Another approach could be using a UI framework like AngularJS + local storage. I'm working on an app right now that will be used online (connected to the web), online locally (connected to a local server that is not connected to the web), and offline.
You could build a single-page web app and let Angular manage all the "urls".

Javascript : Run client side EXE by CHROME [duplicate]

My requirement is to launch my installed application from chrome browser if it is installed on client machine, If not installed then I wanted to start download. What is best recommended solution for chrome?
So fare i tried following
used NPAPI, but due to deprecation of NPAPI by chrome I can't use.
Checked PNacl and Pepper API both API not providing access to local file system to launch an application. They just port my C/C++ code in browser and run it in browser environment with sandbox restrictions.
Is it true only option i have is to use native messaging? Or is there any other option for simple task to launch my application from our url,
Regarding “Native Messaging”
Do users need to install my extension
Do i need to add my extension to chrome store
How to deal with Registry permissions for non admin users
Can i install extension to chrome along with my app installation
Note :- Found some providers use “External Protocol Request” to launch application but there are no enough resources where can i found more about this
Thanks and Regards,
Pravin

For what its worth,
see here - http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/api/nativeMessaging/
the README indicates that Native Messaging can now be added even by non-Admins.
But it appears Native Messaging will only work for Extensions: "Extensions can exchange messages with native applications(...)" and I dont imagine you can expect all of your users to do that.

To open it if it's installed you just need to register your application (at the OS level, so the details will vary by OS; you don't say what OS you are targeting) as a handler for some specific scheme, then have your page open that scheme. That's the same flow that causes mailto: links to open a user's mail client, for instance.

If you have a chrome app, you can use inline install: https://developer.chrome.com/webstore/inline_installation

Web app not working on Chromium in Chrome OS

I'm working on a web app for note-taking called VideoNot.es (http://videonot.es). This app is build with AngularJS and webapp2 and hosted on the Google App Engine.
My app is working fine on Chrome for the major OS (Windows, Mac, Linux) but some users have started to report issues with Chrome OS (mainly teachers with GAFE accounts).
I've decided to run it in Virtualbox and there is effectively an issue.
The app never receives answer send over the Google Channel API (https://developers.google.com/appengine/docs/python/channel/overview) while the backend is logging that it sent it. I had received reports before we moved to it so it is not really link to it.
I really don't understand what is wrong here.
Thanks for your help.

If it's a bug in the Javascript, you'd want to file it on the issue tracker. I haven't noticed much progress on Channel API bugs, so I wouldn't expect much though.
I'd recommend working around it by polling, or another solution, like Node.js hosted elsewhere.