unless it is in the play store you can't sync it. i.e. from phone/tablet to desktop chrome or another device chrome.

To load it at all you have to put chrome in developer mode since you need to side-load the app.

Hey Jerry,

I'd agree with ChatGPT and say this is impossible with a browser extension.  A browser extension would allow you to modify what the browser is showing and it won't modify any data that is living on Googles servers.

I'd think the only way that you could change the subject of an email on the server would be through your email routing settings.  Even through gmails routing I think you can only prepend a custom subject.  However, you cannot remove or edit the subject that the email was sent with.  

Gmail Routing Settings

CloudHQ is making it work. Full Stop.

Prepending might work, but it would have to be AFTER I receive the email the first time. Not sure this will work, unless I'm sending it back to myself. But I need the original sender information for identification along with the subject. So, there may be workarounds, but not the same as CloudHQ's implementation. And… Prepending seems to be available to paid Google Workspace members only. << not sure about this.

I never confirmed whether CloudHQ's Rename Email Subject is persistent across devices, but I do know it is persistent on my Laptop when using Google Chrome Browser to access my Gmail accounts.

Since they are making it work, there is certainly an implementation. Can we figure out what that implementation is?

And they are using only a Browser Extension from the Chrome Web Store! They provide a trial for no charge, then they charge after that.

You'll get access to email routing settings with google workspace, correct.  You should confirm that CloudHQ's rename email subject extension does in fact change the subject of the email on the server because I think the change in subject is only visible locally.  In the case they are actually modifying subjects and updating the server, it would have to be using the Gmail API.  

CONFIRMED:
The emails being modified from my Laptop using CloudHQ are in fact visible on my other device in the Gmail app on my Android Smart Phone.

NOT CONFIRMED:
That observation may not confirm that the subject field has been modified on the Gmail server. But if not, then hard to say how it's being done.

NEW INFORMATION: 
I am new to creating Browser Extensions, and I've discovered where the extension code is stored on my hard drive. The ‘manifest.json’ file contains the ‘name’ variable which identifies the name of the extension which is otherwise buried in a folder whose name is a bunch of random characters.

KRoW - Because of your curiosity, you figured it out. I'll take a closer look at inboxSDK and use ChatGPT to help write the code. This is a whole new area for me. Thank you!

David - Always good to see you. Thank you for contributing.