tab_title_template allow using the 256 terminal colors for formatting

docs/changelog.rst

@@ -81,6 +81,8 @@ Detailed list of changes
 
 - kitten icat: Fix the :option:`kitty +kitten icat --no-trailing-newline` not working when using unicode placeholders (:iss:`7948`)
 
+- :opt:`tab_title_template` allow using the 256 terminal colors for formatting (:disc:`7976`)
+
 0.36.4 [2024-09-27]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

kitty/options/definition.py

@@ -1399,6 +1399,7 @@
 ``{fmt.fg.red}red{fmt.fg.tab}normal{fmt.bg._00FF00}greenbg{fmt.bg.tab}``.
 Similarly, for bold and italic:
 ``{fmt.bold}bold{fmt.nobold}normal{fmt.italic}italic{fmt.noitalic}``.
+The 256 eight terminal colors can be used as ``fmt.fg.color0`` through ``fmt.fg.color255``.
 Note that for backward compatibility, if :code:`{bell_symbol}` or
 :code:`{activity_symbol}` are not present in the template, they are prepended to
 it.

kitty/tab_bar.py

@@ -118,6 +118,8 @@ def __getattr__(self, name: str) -> str:
         elif q == 'tab':
             col = color_from_int((self.draw_data.tab_bg if self.which == '4' else self.draw_data.tab_fg)(self.tab_data))
             ans = f'8{color_as_sgr(col)}'
+        elif q.startswith('color'):
+            ans = f'8:5:{int(q[5:])}'
         else:
             if name.startswith('_'):
                 q = f'#{name[1:]}'