Unable to reproduce the issue on ubuntu 17.10 using chrome reported version #67.0.3396.99 and latest chrome #69.0.3486.0.

Attached a screen cast for reference.

Following are the steps followed to reproduce the issue.
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1. Navigated to chrome://settings/handlers?search=handler, and ensured that no handler is set for mailto links.
2. Opened https://www.w3schools.com/tags/tryit.asp?filename=tryhtml_link_mailto.
3. Clicked the “send mail” link in the right-hand pane.
4. Observed that chrome opened a dialog box asking what application to used to send mail as expected.

ruud@ - Could you please check the issue on latest chrome #69.0.3486.0 by creating a new profile without any apps and extensions and please let us know if the issue still persist or not.

Thanks...!!

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I think the difference is that you have Thunderbird installed and set as the default mail handler through your operating system. Can you check that the following also opens up Thunderbird on that system?

    xdg-open mailto:foo@example.com

In my case, the xdg mailto handler is set to Chrome itself (which makes sense because I have no email clients installed, and many mail clients like Gmail are webapps). I should extend my steps to reproduce with the following step:

 0. Set xdg mail handler to Chrome by running the following command:

    xdg-settings set default-url-scheme-handler mailto google-chrome.desktop

What I think is the issue here, is that Chrome uses the system's default email client to handle mailto links, but the default mail client is Chrome itself, and nothing happens.


Alternatively, the following steps reproduce the same problem:

 0. Set xdg mail handler to Chrome by running the following command:

    xdg-settings set default-url-scheme-handler mailto google-chrome.desktop

 1. Go to chrome://settings/handlers?search=handler, and ensure that no handler is set for mailto links.

 3. Run the following command:

    xdg-open mailto:foo@example.com

What is the expected behavior?
Chrome should ask how to open the mailto link.

What went wrong?
A new empty browser window popped up. Nothing else happened.


Note that this issue is not specific to Linux, I have seen people using Windows 10 experience the same issue. In that case, the default email client was also set to Chrome in the Windows settings. The mechanism may be different (xdg on Linux, some other OS facilities on Windows) but the end result is the same: Chrome opens the system's default email client, which is Chrome itself, and because no handler is set for mailto links, nothing happens.

Thank you for providing more feedback. Adding the requester to the cc list.

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

** Mass UI Triage **

We were unable to reproduce this bug in (Linux 14.04 LTS) OS. If this bug still reproduces for you, 
please reopen or file a new issue. Thanks!

This issue was not resolved, and the steps to reproduce that I posted in comment 3 still apply. Because I am unable to re-open this, I filed  crbug.com/906603 .

 Issue 906603  has been merged into this issue.

Reopening since I think this is a legitimate issue. However, it's quite complex.

In summary, if Chrome has no mailto handler set, we fall back to the OS mail handler. However, there are some bad edge cases:

- If the OS has no mail handler set, we do nothing. (Not sure what happens on Windows / macOS.)
- On Chrome OS, there is no OS concept of a mail handler. We just open a new tab with "mailto:" in the URL bar and a blank page.
- On Linux, we call xdg-open so we don't actually know which app it's going to try and run.
- If Chrome is set as the OS's mailto handler, but Chrome doesn't have a mailto handler set, we bounce through the OS back into Chrome and it does nothing.

We should at least be able to detect some of the above edge cases and show a dialog that there is no mailto handler set. Showing a dialog that lets you choose a mailto handler is much trickier, since we'd need to index some or hard-code some.

+groby do you think this is something we should fix?

I'm putting it onto the triage queue. (But I'm not sure it's a high value feature)

Meanwhile, adding cyflee as a heads up (should the new welcome flow set mailto:// handlers? If so, please add a bug)

Thanks groby. This is something we considered in the new onboarding flow but is low on the priority list. Opened a tracking bug here: https://bugs.chromium.org/p/chromium/issues/detail?id=919128