diff --git a/lib/extension/window.js b/lib/extension/window.js
index 61820e1e..f7f58dff 100644
--- a/lib/extension/window.js
+++ b/lib/extension/window.js
@@ -103,8 +103,13 @@ export class WindowManager extends GObject.Object {
     let wmId = metaWindow.get_id();
 
     for (let override of overrides) {
-      // if the window is already floating
-      if (override.wmClass === wmClass && override.mode === "float" && !override.wmTitle) return;
+      // if the window is already floating: for Super+C only a rule for this very window counts
+      // (another window of the app may float already, #492), for "always float" only a rule for
+      // the whole app (not one that Super+C made for a single window)
+      if (override.wmClass === wmClass && override.mode === "float" && !override.wmTitle) {
+        if (withWmId ? override.wmId !== wmId : override.wmId) continue;
+        return;
+      }
     }
     overrides.push({
       wmClass: wmClass,
@@ -128,7 +133,9 @@ export class WindowManager extends GObject.Object {
           override.wmClass === wmClass &&
           // rules with a Title are written by the user and peristent
           !override.wmTitle &&
-          (!withWmId || override.wmId === wmId)
+          // Super+C: this window's rule; "always float": the app's rule (and this window's own),
+          // not the rules Super+C made for its other windows
+          (withWmId ? override.wmId === wmId : !override.wmId || override.wmId === wmId)
         )
     );
 
@@ -757,7 +764,12 @@ export class WindowManager extends GObject.Object {
             focusNodeWindow.rect = this.tree.processGap(focusNodeWindow);
           }
           if (!focusNodeWindow.isFloat()) {
-            this.addFloatOverride(focusNodeWindow.nodeValue, false);
+            // Float this window, as Super+C does: a rule for this window only (not for its whole
+            // app, which was saved for good and Super+C couldn't remove), applied right away (or
+            // the next render tiled it again) (#469)
+            this.addFloatOverride(focusNodeWindow.nodeValue, true);
+            this.windowProps = this.ext.configMgr.windowProps;
+            focusNodeWindow.mode = WINDOW_MODES.FLOAT;
           }
           this.move(focusNodeWindow.nodeValue, focusNodeWindow.rect);
           this.queueEvent({