Interesting thought.  Presumably installing the extension through the inline installation installs it to the underlying profile, which is also a little weird.  Antony, Ben, any opinions here?

For consistency sake, I think it makes sense. Its a little weird that currently it's possible to inline install in incognito mode and attach it to your profile.

There's also a few other concerns here.  For instance, we shouldn't just silently fail - we should let the user know somehow that the extension wants to be installed.  Perhaps just redirect automatically to the webstore?  We also need to figure out the response to the API call.  In theory, we don't want incognito to be easily identified by websites (I know there are already ways, but we don't want to add more), so we can't return an error saying "Sorry, the user is in incognito mode".

> Perhaps just redirect automatically to the webstore?

That sounds like the least disruptive and most logical solution :)

> In theory, we don't want incognito to be easily identified by websites

Huh, great point, not sure what to do about that. Adding Privacy label just in case.

Yeah, since we don't allow install from the regular webstore in incognito, I agree that we shouldn't allow inline install. I agree that opening up a non-incognito tab to the webstore entry is probably the right solution. As for the response to the API call initiating the install, I think it would be reasonable to return the user cancelled string.

The userCanceled enum seems too specific in this scenario.  Would you consider otherError or something similar instead?  I understand the need to keep it ambiguous, but a well thought out message in response to userCanceled could be very different from otherError.  Such as:  
a. userCanceled - a tooltip popup telling the user where to install the extension if they change there mind. 
b. otherError - a "something went wrong" error message that informs the user of potential problems with the installation, such as being in incognito mode or using an old version of chrome (not sure if that's a real scenario).

Some generic error message would be fine, but as Devlin mentioned in (3) we'd probably want to make sure it was an error message that could occur for other reasons so that it wasn't a reliable way to determine if the user was using an incognito window. 

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

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This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Inline install is deprecated.

https://blog.chromium.org/2018/06/improving-extension-transparency-for.html

Closing this out.