The Website link from the manage page can no longer be opened using middle click on latest Nightly builds

[SoftVision-CosminMuntean]

[Regression]:

• This issue is not reproducible on Firefox versions lower than 68. Considering this using mozregression tools I have managed to find the pushlog with the changes that caused this regression.
• Here is the pushlog: https://tinyurl.com/y6kndlly
• It seems that bug 1379466 introduced this issue on Firefox 68.

[Affected Versions]:

• Lockwise 2.2.0-alpha
• Nightly 68.0a1

[Affected Platforms]

• All Windows
• All Mac
• All Linux

[Perquisites]

• Have the latest Firefox 68 version installed.
• Have the Lockwise 2.2.0 - alpha extension installed.
• Have multiple saved logins.

[Steps to reproduce]:

1. Open the Firefox browser with the profile from prerequisites.
2. Click the "Lockwise" toolbar button and click the "Open Lockwise" button from the doorhanger.
3. Click one of the saved logins from the manage page.
4. Middle click on the website link.
5. Observe the behavior.

[Expected results]:

• The website is opened in a new tab.

[Actual results]:

• Nothing happens.

[Notes]:

• The issue is also reproducible if you try to open the website by pressing the "Ctrl" key + "Left Click". The website is not opened.
• Attached a screen recording with the issue:

[SoftVision-CosminMuntean]

Since this is a Firefox issue I have also logged the bug in Bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1556658.