Revert "Hide menu bar icons with a cover instead of moving them off screen"

This reverts commit 3e57efe312.

README.md

@@ -23,24 +23,30 @@ permission (System Settings → Privacy & Security → Accessibility). The panel
 prompts for it; without it the Menu Bar section is empty and everything else
 still works.
 
-## Hiding menu bar items
+## Hiding menu bar items (best-effort)
 
-macOS has no public API to move another app's status item. Instead of moving
-them, the **Hide items from the menu bar** toggle (on by default, remembered)
-draws a frosted **cover** window over the other apps' icons. They keep their real
-positions, so tapping a tile in the panel opens that app's menu in the right
-place with **no flicker**, and the cover leaves a gap for the hamburger so it is
-never hidden.
+macOS has no public API to move another app's status item. The **Hide items from
+the menu bar** toggle uses the spacer technique: a zero-width status item is
+created at launch whose length is expanded to push the other icons off-screen so
+they only live in this panel. It is **on by default** (the choice is
+remembered), always undone on quit, and if the app dies macOS removes the spacer
+automatically.
 
-What it does and does not cover:
+What it can and cannot hide:
 
-- Covers **other third-party apps' icons** (cmux, Kapture, WireGuard, input
-  source, Now Playing, …).
-- Keeps **Wi-Fi, Spotlight, Clock, Battery and Control Center** visible — macOS
-  reserves that far-right area, so those icons stay put.
-- The cover matches the menu bar's frosted look only approximately; over an
-  unusual wallpaper the covered strip may be slightly visible.
-- Turning the toggle off removes the cover immediately; quitting does too.
+- It hides **other third-party apps' icons** (cmux, Kapture, WireGuard, input
+  source, Now Playing, …) so only your apps' icons leave the bar.
+- It **keeps Wi-Fi, Spotlight, Clock, Battery and Control Center**. The spacer's
+  boundary is tuned (preferred position 250) to fall just left of Wi-Fi, so the
+  Apple items on the right stay visible. macOS reserves that far-right area: a
+  third-party item can never be placed to the right of it, so those icons cannot
+  be pushed away even in principle. (Bartender and Ice hit the same wall and
+  cover the area with their own overlay bar instead.)
+- Newly launched apps are placed to the left of the spacer, so they are hidden
+  automatically.
+- Advanced: set `defaults write dev.tzgyn.simpletopbar debug.spacerPos -float <n>`
+  to move the boundary (larger = keep more icons; > ~400 starts leaking app
+  icons back into the bar).
 
 ## Install with Homebrew