diff --git a/share/functions/__fish_theme_cat.fish b/share/functions/__fish_theme_cat.fish
index 21f7176df..79dc363c1 100644
--- a/share/functions/__fish_theme_cat.fish
+++ b/share/functions/__fish_theme_cat.fish
@@ -6,15 +6,16 @@ function __fish_theme_cat -a theme_name
         echo >&2 Searched (__fish_theme_dir) "and `status list-files themes`"
         return 1
     end
-    set -l theme_data (__fish_config_with_file $theme_path cat)
+    set -l theme_data (if string match -q '/*' -- $theme_path; cat $theme_path; else status get-file $theme_path; end)
     set -l allowed_lines \
         '\s*' \
         '\s*#.*' \
         '\[(dark|light|unknown)\]' \
         (__fish_theme_variable_filter)
     set allowed_lines "^($(string join -- '|' $allowed_lines))\$"
-    for line in $theme_data
-        string match -rq -- $allowed_lines $line
+    printf '%s\n' $theme_data | string match -rvq -- $allowed_lines
+    and for line in $theme_data
+        string match -rq -- $allowed_lines $theme_data
         or printf >&2 "error: unsupported line in theme '%s': %s\n" $theme_name $line
     end
     string join \n $theme_data
diff --git a/share/functions/fish_config.fish b/share/functions/fish_config.fish
index 801db489e..b0b0c0221 100644
--- a/share/functions/fish_config.fish
+++ b/share/functions/fish_config.fish
@@ -287,7 +287,7 @@ function __fish_config_theme_choose
 
     set -l color_theme
     __fish_config_theme_canonicalize
-    set -l theme_data (type -q cat && __fish_theme_cat $theme_name)
+    set -l theme_data (__fish_theme_cat $theme_name)
     or return
     set -l color_themes dark light unknown
     set -l theme_is_color_theme_aware false
@@ -340,7 +340,7 @@ function __fish_config_theme_choose
         end
 
         set -l color_theme
-        string join \n -- $theme_data |
+        string match -re -- (__fish_theme_variable_filter)'|^\[.*\]$' $theme_data |
             while read -lat toks
                 if $theme_is_color_theme_aware
                     for ct in $color_themes
@@ -354,8 +354,8 @@ function __fish_config_theme_choose
                     end
                 end
                 set -l varname $toks[1]
-                string match -rq -- (__fish_theme_variable_filter) "$varname"
-                or continue
+                string match -q '[*' -- $varname
+                and continue
                 # If we're supposed to set universally, remove any shadowing globals
                 # so the change takes effect immediately (and there's no warning).
                 if test $scope = -U; and set -qg $varname