Windows program to remove titlebar, frame, etc from a window?

"Just something small that I made for my purposes after reading voodoomsr's comment. Makes it to go left up corner and resizes to my full resolution. Restores as it was before. Can't be used with multiple apps same time.

Thanks voodoomsr

;-Caption
LWIN & LButton::
SetTitleMatchMode, 2
WinGetPos, X, Y, Width, Height, A
WinSet, Style, -0xC00000, A
WinMove,A,,0,0,1920,1080
return
;

;+Caption
LWIN & RButton::
WinSet, Style, +0xC00000, A
WinMove,A,,%X%,%Y%,%Width%,%Height%
Sleep, 1000
Sleep, 1000
return
;

EDIT:

TBH I tried to find something useful for windows that doesn't resize but couldn't find anything (not saying that it's not possible, this was actually my first Autohotkey script).

Well anyhow I made some tweaks like removing unnecessary sleeps, using style that Nelson suggested and making it work with only one button so double-clicking won't override saved variables.

#SingleInstance force

; Exclude the desktop
; Note: Also excludes ""My Computer"" browsing windows.
; Better detection might be needed to differentiate the parent explorer ""ahk_id"" from child windows.
; Also seems to disregard accidental Metro interface clicks (Win 8+)
#IfWinNotActive ahk_exe explorer.exe

; Set your resolution (minus decorations like start bars if you wish to leave those on-screen.
w = 1920
h = 1080
w_wasted = 6 ; width used by resize bars
h_wasted = 29 ; width used by caption frame and resize bars

; Window to fullscreen
LWIN & LButton::
SetTitleMatchMode, 2
WinGet Style, Style, A

; 0xC40000 = WS_BORDER (0x800000) + WS_DLGFRAME (0x400000) + WS_SIZEBOX aka WS_THICKFRAME (0x040000)
if(Style & 0xC00000) { ; if has WS_CAPTION. Ignore sizebox value.
WinGetPos, X, Y, Width, Height, A
WinSet, Style, -0xC40000, A ; removes attributes, including sizebox...doesn't do a strict subtraction
WinMove,A,,0,0,w,h
} else {
WinSet, Style, +0xC40000, A
; Note: will set WS_SIZEBOX even if not previously present
if(Width > w - w_wasted) {
Width := %w%-%w_wasted%
}
if(Height > h - h_wasted) {
Height := %h%-%h_wasted%
}
WinMove,A,,%X%,%Y%,%Width%,%Height%
}
WinSet Redraw
Return"

"here is a programm that can remove the titlebar for any window.
To do that you must select games window in WinExplorer tree view than switch to 'Style' tab and check off WS_DLGFRAME."

"i found this at the HydrogenAudio forums:

Here's a screenshot of Foobar 2000 without a window title bar:

The program used is called Flash Desktops (shareware)

Unfortunately they don't really elaborate on the program settings to achieve the goal but rather on the problem of moving windows without a titlebar. WindowBlinds is also mentioned."

"If you can code and you are running Vista or newer it's pretty easy to make a program that registers a DWM thumbnail to the application and then you can select to only show the window content without borders in this thumbnail.
You also have to forward all input from this overlaying program to the game in some way but that's not super complicated either."

I no longer run Windows so can't test this, but Borderless Gaming is a promising-looking open source app that solves this problem. It shows a list of running applications and lets you select one to manipulate the windows.