Code to demonstrate issue...
New-style code (won't run on old versions)...
#SingleInstance force #Persistent SetTimer, Timer, -3000 msgbox, 64, , (LTrim % Keep this window open for 3 secs & the WinWait causes 100% CPU Close it before 3 secs & the WinWait will use 0% CPU ) return Timer: Tooltip, WinWait running... WinWait, % "PLEASE USE 100% CPU FOR NO REASON" msgbox, WinWait done returnOld-style code (so I could test on older versions)...
#SingleInstance force #Persistent SetTimer, Timer, 3000 msgbox, 64, , Keep this window open for 3 secs & the WinWait causes 100`% CPU`n`nClose it before 3 secs & the WinWait will use 0`% CPU return Timer: SetTimer, Timer, Off Tooltip, WinWait running... WinWait, PLEASE USE 100`% CPU FOR NO REASON msgbox, WinWait done returnThis was 1st noticed using a FileSelectFile dialog (Open/Save Common Dialog {GetOpenFileName()}) with AutoHotkey_L 1.1.05.01...but I've done more testing & narrowed the regression range to...
OK - 0% CPU - AutoHotkey 1.0.44.10
BAD - 100% CPU - AutoHotkey 1.0.44.11...I have a diff of the source code between those versions, if that'll help...
The 1.0.44.11 changelog says...
1.0.44.11 - September 9, 2006
[*:254m42ym]Fixed FileSelectFolder and TreeView to respond properly to mouse clicks when timers are running.
[*:254m42ym]Fixed inability of OnMessage() to consistently monitor certain messages such as WM_NOTIFY. [thanks numEric]
[*:254m42ym]Fixed inability of literal/quoted strings to contain `%.
[*:254m42ym]Fixed continuation sections to support #EscapeChar, #DerefChar, and #Delimiter. [thanks Laszlo]
[*:254m42ym]Changed GroupBox to default to "no word-wrapping". This can be overridden via +Wrap.
[*:254m42ym]Changed/improved the ** operator and "Transform Pow" to support negative bases when the exponent isn't fractional. [thanks Laszlo]
[*:254m42ym]Improved GUI responsiveness during UrlDownloadToFile (especially for slow downloads)....I'm guessing that FileSelectFolder fix broke WinWait?