A popup begun outside any window, as the context menus of the editor, the dialogs for a new scenery and for opening one and the
pause dialog of the driver are, takes no viewport from a parent. It was put into the main window only where it merged there:
with the main window minimized, or behind a panel taken out into a window of its own, it got a window of the system of its own,
with an OpenGL context of its own, the way the editor froze. With io.ConfigViewportsNoAutoDetach the tooltips and popups stay in
the main window there too.
The comment of io.ConfigViewportsNoAutoDetach tells how they're placed: as with the viewports off, not shrunk.
io.ConfigTooltipsWrapWidth moves to the miscellaneous options, it works with the viewports off as well, and its comment tells
that SetItemTooltip() wraps too and BeginTooltip() doesn't.
With the panels in separate windows on (the default), a tooltip or a popup that didn't fit in the main window got a window of
the system of its own, with an OpenGL context of its own. The editor froze so on 2026-11-08: its main thread stuck for good in
the NVIDIA driver while making the context of an invisible window 1925 x 29 px, a tooltip in one line wider than the screen.
The Polish texts of the editor have tooltips of up to 360 characters in a line; the one of the curve mode of laying track is
2088 px wide.
- io.ConfigViewportsNoAutoDetach (a MaSzyna addition, set with the separate windows) keeps the tooltips and popups shown over
the main window inside it too, placed and shrunk as they are without the separate windows: they get no viewport of their
own. A panel dragged out of the main window by hand still gets its window, and the tooltips and popups over it may go past
its edge as before.
- io.ConfigTooltipsWrapWidth (a MaSzyna addition): SetTooltip() wraps its text at this width. The ui sets 40 em, 520 px at the
font of 13 px.
Checked in the editor on a hidden desktop: the tooltip of the curve mode, full screen 1920 x 1080, and the one of the redo
button at the edge of a window 1280 x 720 each made a window of their own before, and none now. Both are drawn in the main
window, the long one in five lines.
Pulling a panel's grip into the corner of the screen pushed it a couple of
pixels past the main window, and ImGui gave it an OS window of its own. Now
a panel only comes out when dragged with the cursor outside the main window.
A panel that stays in the main window needs its grips in reach, so a resize
stops at the edge, and a panel left past the edge or too big for the window
is moved back and shrunk to fit.
This is a new io.ConfigViewportsNoAutoDetach option in our copy of ImGui, so
it has to be carried over when ImGui gets updated. ImGui itself has no option
for this, as of 1.93.1.
