diff --git a/run.go b/run.go
index 003d199f2..62e0e8a3c 100644
--- a/run.go
+++ b/run.go
@@ -105,6 +105,8 @@ var theUIContext atomic.Value
 //
 // On browsers, the scale is automatically adjusted.
 // It is strongly recommended to use iframe if you embed an Ebiten application in your website.
+// scale works as above as of 1.10.0-alpha.
+// Before that, scale affected the rendering scale.
 //
 // On mobiles, if you use ebitenmobile command, the scale is automatically adjusted.
 //
@@ -220,6 +222,8 @@ func SetScreenSize(width, height int) {
 //
 // On browsers, SetScreenScale saves the given value and affects the returned value of ScreenScale,
 // but does not affect actual rendering.
+// SetScreenScale works as above as of 1.10.0-alpha.
+// Before that, SetScreenScale affected the rendering scale.
 //
 // On mobiles, SetScreenScale works, but usually the user doesn't have to call this.
 // Instead, ebitenmobile calls this automatically.
@@ -269,10 +273,13 @@ func SetCursorVisibility(visible bool) {
 	SetCursorVisible(visible)
 }
 
-// IsFullscreen returns a boolean value indicating whether
-// the current mode is fullscreen or not.
+// IsFullscreen reports whether the current mode is fullscreen or not.
 //
-// IsFullscreen always returns false on browsers and mobiles.
+// IsFullscreen always returns false on browsers.
+// IsFullscreen works as above as of 1.10.0-alpha.
+// Before that, IsFullscreen reported whether the current mode is fullscreen or not.
+//
+// IsFullscreen always returns false on mobiles.
 //
 // IsFullscreen is concurrent-safe.
 func IsFullscreen() bool {
@@ -287,7 +294,11 @@ func IsFullscreen() bool {
 // On desktops, Ebiten uses 'windowed' fullscreen mode, which doesn't change
 // your monitor's resolution.
 //
-// SetFullscreen does nothing on browsers or mobiles.
+// SetFullscreen does nothing on browsers.
+// SetFullscreen works as above as of 1.10.0-alpha.
+// Before that, SetFullscreen affected the fullscreen mode.
+//
+// SetFullscreen does nothing on mobiles.
 //
 // SetFullscreen is concurrent-safe.
 func SetFullscreen(fullscreen bool) {