as it wasn't necessary and turns out it causes problems with event routing when the parent <label> includes a <button> which we use now instead of dummy links
* same color for disabled styles in popup/manager
* reduce slider knob
* fix click-to-edit in popup on slider and iframe badge
* indicate slider interactivity on hovering name
* remove 2px gap when first/last entry is striped
* stretch 'blocked' separator to full width
* unreachable dimming should not apply to frames
* restore CWS check in popup
* increase not-applied opacity on name as it's #999 now
* oldUI: restore 'disabled' bubble + show 'usercss' fully
* adjust disabled colors to match perception because transparent text is rendered using gamma-blending whereas colored text uses LCD-antialiasing so to match opacity .6 of #000 we need #888 not #666
* also apply live-preview if an unsaved style was disabled
* use box-shadow instead of outline for focus everywhere
* allow focus outline on click in text/search input or textarea
* search inputs should use the same style as text inputs
* also use box-shadow focus on delete buttons
* remove URLSearchParams workaround, not needed since Chrome 55
* use `once` in addEventListener, available since Chrome 55
* update USO bug workarounds, remove obsolete ones
* ping/pong to fix openURL with `message` in FF
* use unprefixed CSS filter, available since Chrome 53
* use unprefixed CSS user-select, available since Chrome 54
* focus tweaks
* also use text query in inline search for Stylus category
* use event.key, available since Chrome 51
Co-authored-by: narcolepticinsomniac