If Screenshots is first used on a non-standard web page, the Screenshots "#hello" page is wrongly opened in a new tab

[Softvision-CristinaBadescu]

[Notes]:

• This issue is not reproducible if you use the context menu option.

[Affected versions]:

• Nightly 60.0a1
• Screenshots v31.1.0 dev

[Affected Platforms]:

• All Windows
• All Mac
• All Linux

[Prerequisites]:

• Have the "xpinstall.signatures.required" pref set to "false" and "extensions.legacy.enabled" pref set to "true".
• Have the latest Firefox Screenshots v31.1.0 installed from here on a new clean profile.
• Firefox Screenshots has not been used.

[Steps to reproduce]:

1. Open Firefox browser with the profile from prerequisites and navigate to a non-standard web page such as https://addons.mozilla.org/en-US/firefox/.
2. Click the "Page actions" menu.
3. Select "Take a Screenshot" option and observe the behavior.

[Expected result]:

• "We can't screenshot this page." notification appears.

[Actual result]:

• A new tab is opened and you are redirected to the "https://screenshots.firefox.com/#hello" page.

[Additional notes]:

• Here is a screen recording with the issue:
  

[johngruen]

We should redirect to onboarding from the context menu as well.

[testeaxeax]

My fix shows the "We can't screenshot this page." notification and then opens "https://screenshots.firefox.com/#hello" to perform onboarding. It works via the "Page actions" and the context menu.

[Softvision-CristinaBadescu]

This issue has been partially fixed: if you use the context menu option or the option from the "Page actions" menu, you are redirected to the "#hello" page, but the notification ("We can't screenshot this page.") is not displayed. Tested using the latest Firefox Screenshots v32.1.1 installed from here, on latest Nightly build 62.0a1 (2018-05-09), on Windows 10 x64, Mac 10.12.6 and Arch Linux 4.12.

Considering this, I'm going to reopen the issue.

[testeaxeax]

@Softvision-CristinaBadescu Screenshots isn't supposed to show an error message, see here.

[Softvision-CristinaBadescu]

All right. Considering the fact that the error message should not be displayed, I'm going to close the issue. Thanks!

[SoftVision-CosminMuntean]

I have verified this issue on latest Screenshots (33.0.0) dev version installed on latest Nightly (62.0a1) build and the issue is no longer reproducible.
Tested on Windows 7 x64, Arch Linux and Mac 10.13.