If the 2nd website is an about: * page, its content wrongly overlaps the 1st one when the split tabs are resized

[Softvision-CristinaBadescu]

[Affected versions]:

• Nightly 60.0a1
• Tab Split 0.1.7

[Affected Platforms]:

• All Windows
• All Mac
• All Linux

[Prerequisites]:

• Have a clean Firefox profile with the latest Tab Split v0.1.7 installed.

[Steps to reproduce]:

1. Open Firefox browser with the profile from prerequisites and navigate to a website.
2. Click the "Tab Split" button from the toolbar.
3. Navigate to a website.
4. Drag the colored frame to the right and observe the page content.

[Expected result]:

• The content is smoothly rendered.

[Actual result]:

• The content jumps around and overlaps the other website's content for short moments.

[Notes]:

• Here is a screen recording with this issue:

[Softvision-CristinaBadescu]

This issue is reproducible using Tab Split v0.1.9 only if the 2nd tab contains "about: **" pages, on latest Nightly 60.0a1 (2018-02-22), on Windows 10 x64, Mac 10.12.6 and Ubuntu 14.04 x64. Considering this, I'm going to change the title.