Firefox 57 / Quantum: emulate print styles

问题:

How can I emulate the media type "print" in the new Firefox Quantum dev console?

Tried to enable it somehow and searched the documentation but couldn't find any hints!

回答1:

I thought it's impossible. But suddenly have found answer in another topic:

1. press Shift + F2 to get special browser console
2. type "media emulate print"
3. hit "Enter"

That's it.

[UPD] this console has gone starting from v62. There are tiny chances to get this feature back according to https://discourse.mozilla.org/t/how-to-media-emulate-print-without-developer-toolbar-gcli/30975

回答2:

After the GCLI (Developer Toolbar) has been removed, the feature is now once again available in the latest nightly version of Firefox. Print style emulation can now be toggled from the styles panel in the Inspector of the Developer Tools. It's the little page icon in the upper right, next to the buttons to change the hover state, toggle classes and add CSS rules (toggled active in the screenshot):

As of May 2019, this has not yet landed in the current stable release (66), but it is available in the current Developer Edition and the Nightly Channel (68.0a1 and above).