Merge from 3.5 for issue #26664
diff --git a/Lib/venv/scripts/posix/activate.fish b/Lib/venv/scripts/posix/activate.fish
index fb7f5c0..45391aa 100644
--- a/Lib/venv/scripts/posix/activate.fish
+++ b/Lib/venv/scripts/posix/activate.fish
@@ -55,8 +55,8 @@
     # with the original prompt function renamed, we can override with our own.
     function fish_prompt
         # Prompt override?
-        if test -n "$__VENV_PROMPT__"
-            printf "%s%s%s" "$__VENV_PROMPT__" (set_color normal) (_old_fish_prompt)
+        if test -n "__VENV_PROMPT__"
+            printf "%s%s%s" "__VENV_PROMPT__" (set_color normal) (_old_fish_prompt)
             return
         end
         # ...Otherwise, prepend env