Describe the issue:

Not sure whether this is an issue or feature of the non-legacy version of uBO, but when in uBO in "3rd party filters" tab, no filters are used (Static filters: 0 ÷ Cosmetic filters: 0 from:), when I right click on any element on any website and choose 'Block element' from context menu, nothing happens. Additional sub-issue: on uBO 1.13.10 there is also uBlock icon missing in front of "Block element" command.

One or more specific URLs where the issue occurs:

Any website.

Your settings:

• OS/version: Windows 7 SP1 64bit Ultimate PL
• Browser/version: Firefox 55.0.3 32bit (e10s enabled) / FF Nightly 56.0b8 64bit + uBO above v1.13.8

Settings on which the issue doesn't occur:

• Browser/version: Opera 47.0.2631.71 64bit (PGO) + uBO any version.
• Browser/version: Firefox 55.0.3 32bit (e10s enabled) / FF Nightly 56.0b8 64bit + uBO v1.13.8 and below

Additional comments:

Seems like not a critical bug, but rather cosmetic, since almost everyone have more than 0 filters active, thus that's why I've discovered the bug while in debug/testing mode (and this mean I've had all filters disabled). But whether the error is not more serious, the creator finds, because the bug may be related to other bugs and break some other things.