Dark Blue Refresh 2023 wót Dan

Changelog for sleek v5.4 "Blue Refresh 2023" (with example screenshots!):

1. added slight blue vertical separator line between tab list and url bar
2. removed URL bar field box

Changelog for sleek v5.3 "Blue Refresh 2023" (with example screenshots!):

1. marked suggestion entry from URL bar now in more noticable yellow than bright "alien-blue"

Changelog for v5.2 "Blue Refresh 2023":

1. dark blue background in bookmark popup menu

2.
- blue background behind selected address bar suggestion
- selected address bar suggestion text appears in light-blue

3. noticable blue toolbar field border for more precise border of "drag & drop window" area

____________________________________________________________________________________
formerly: dark blue K theme dark-blue-k-theme