Strict blocking does not work for "open in new tab" on mobile

[gwarser]

Details

### Prerequisites - [x] I performed a cursory search of the issue tracker to avoid opening a duplicate issue - Your issue may already be reported. - [x] I also searched the existing issues at - [x] This is not a support issue or a question - Support issues and questions are handled at [/r/uMatrix](https://old.reddit.com/r/uMatrix/) - I tried to reproduce the issue when... - [x] uMatrix is the only extension - [ ] uMatrix with default lists/settings - [ ] using a new, unmodified browser profile - [x] I am running the latest version of uMatrix - [x] I checked the [documentation](https://github.com/gorhill/uMatrix/wiki) to understand that the issue I report is not a normal behavior - [ ] I used the logger to rule out that the issue is caused by my ruleset

Description

https://www.reddit.com/r/uMatrix/comments/fvk1p5/root_document_rules_are_not_being_applied_to/

Using "doc block" rule: * * doc block

When I open a link via "new tab" uMatrix does not stop me from going to an unknown site. However, when I open the link by just clicking, the site does not load (the "uMatrix has prevented the following page from loading" warning appears).

From log it looks like this doc request is classified as behind-the-scene.

Toggling matrix-off: behind-the-scene to false block the request (log says so), but page is blank (and for some reason I see page preview in tabs view, but can be cached thumbnail). Reloading makes it about:blank.

Dev version of uM also opens blank page.

A specific URL where the issue occurs

https://www.theguardian.com/film/filmblog/2014/apr/10/reel-history-noah-drowning-unbiblical-detail -> http://www.screenonline.org.uk/tours/hitch/tour6.html

Steps to Reproduce

1. add rules:

   * * doc block
   theguardian.com theguardian.com doc allow

2. open https://www.theguardian.com/film/filmblog/2014/apr/10/reel-history-noah-drowning-unbiblical-detail

3. tap&hold on hyperlink in the webpage labeled "MacGuffin" to open in new tab

Ruleset

Default plus:

* * doc block
theguardian.com theguardian.com doc allow

Supporting evidence

12:51:43    www.theguardian.com     image   https://i.guim.co.uk/img/static/sys-images/Guardian/Pix/pictures/2014/4/8/1396973538032/Noah-Tubal-Cain-Ray-Winst-008.jpg?width=445&quality=45&auto=format&fit=max&dpr=2&s=daccdb91873ac351011c48e966aaa7f2 3p
12:51:43    www.theguardian.com     image   https://i.guim.co.uk/img/static/sys-images/Guardian/Pix/pictures/2014/4/8/1396973103134/Noah-Russell-Crowe-in-Dar-013.jpg?width=465&quality=45&auto=format&fit=max&dpr=2&s=a17d3595697f9d8b78b8e0c95b2ae52a 3p
12:51:18    www.screenonline.org.uk     css http://www.screenonline.org.uk/tours/hitch/tour6.html{inline_style} 
12:51:18    www.screenonline.org.uk     script  http://www.screenonline.org.uk/tours/hitch/tour6.html{inline_script}    
12:51:18    www.screenonline.org.uk --  script  http://www.google-analytics.com/ga.js   3p
12:51:17    www.screenonline.org.uk     css http://www.screenonline.org.uk/css/bfi_global.css   
12:51:17    www.screenonline.org.uk     css http://www.screenonline.org.uk/css/backward.css 
12:51:17    behind-the-scene        doc http://www.screenonline.org.uk/tours/hitch/tour6.html   3p

Your environment

• uMatrix version: 1.4.0
• Browser Name and version: Firefox 68.6.0esr
• Operating System and version:

[rjameson3]

I am trying to find if my issue is the same or not before opening a new ticket/bug report - but every tab for past week, FF & Chrome, new site or newly opened tab from my past has uM disabled. Only way to fix was to reset all uM settings/rules etc. Sounds like this ticket except not on mobile.

[gorhill]

Only way to fix was to reset all uM settings

Sounds like you had a global rule to disable matrix filtering, matrix-off: * true: