extensions.stylish.editorWindowMode=0 [show editor in a tab (default)] not followed if no userstyles installed, editor opens in separate window instead · Issue #248 · stylish-userstyles/stylish · GitHub

(full Imgur album) userstyles.org - Using Stylish for Firefox: Hidden Stylish preferences extensions.stylish.editorWindowMode Whether to show the editor in a tab (0) or in a separate window (1). By default this preference is set to 0 (so

Moving User Styles (Themes) from Stylish 3.x to Stylus

Stylish to Stylus Migration (How To / Help) - Add-on Support - Mozilla Discourse

How can I make a window appear on top of another window, without closing when I click the second? - Super User

New window without toolbar – Get this Extension for 🦊 Firefox (en-US)

Optional changing station titlePreface on extension opening/close for easy hiding horizontal tabs · Issue #214 · mbnuqw/sidebery · GitHub

extensions.stylish.editorWindowMode=0 [show editor in a tab (default)] not followed if no userstyles installed, editor opens in separate window instead · Issue #248 · stylish-userstyles/stylish · GitHub

Tabliss does not set the homepage for new windows on Firefox · Issue #182 · joelshepherd/tabliss · GitHub

Window title · Issue #9 · Lej77/tree-style-tab-in-separate-window · GitHub

Clean up the inconsistent Windows UI style usage · Issue #3508 · notepad-plus-plus/notepad-plus-plus · GitHub

stylish intermittently stops applying to links opened to new tabs in Safari 11 · Issue #34 · 350d/stylish · GitHub