This happens for me as well. During heavy usage with quick turning the mouse escapes the window. Other native games using libraries such as SDL do not produce this side effect.

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@imYEA
I think your issue was different from this one though. It sounds like your mouse stopped working indefinitely, the issue here is that it only stops temporarily, it's not permanent.

Even in fullscreen if I flick my mouse to the left for example, I can no longer move my screen until I move my mouse to the right a bit then it's like the mouse engages again.

Yeah, that is a different problem from this one. I've actually had the mouse completely fail as you've described imYEA. My solution was to fidget with the settings in-game until it somehow reset. My mouse tends to leave the window anytime a large amount of new objects come into view. So I can only suspect that whatever loop is locking the mouse within the window is actually lagging with the game, letting it release momentarily.

This problem actually existed for me under Wine, as well. And I've always chalked it up to that, until now.

yes i was playing counterstrike and took hit the print screen button on accident. upon doing this the default screenshot saver program opened up and minimized cs. when i opened cs back up i noticed i could not turn around at all. i disconnected and reconnected and noticed no change. i opened options and closed it. no change.

I think this issue actually has nothing to do with steam now.

I've only been playing steam games, but I just played Quake Live and it was happening there too. I am absolutely sure this never happened before, so it must have been a system update that caused this to happen system wide.

I guess the bug can be closed now. Those of you who were posting about the mouse completely failing might consider searching for the appropriate bug report or creating one because that's not what this issue was about.
However, I did notice your bug as well but for me it was due to changing desktops and steam thinking the ALT key was still being held down. Simply pressing alt fixed it, so you could try pressing your modifier keys next time it happens and see if it fixes it.

I've seen a "mouse pops out of window" sometimes in Minecraft, (also using nvidia drivers). Usually it's caused by clicking and moving the mouse at the same time. (Which is likely to be happening when you've got a stone sword and a creeper is close by.)

Also, possibly related: TF2 displays a similar problem to Solar 2 in that both tend to have weird handling of the mouse (where the mouse pointer is pointing at one area of the window, but the window thinks I'm pointing at another area), and problems getting the game to switch resolutions.

Yes apparently its kernel issue we have to all address
On Feb 27, 2013 12:49 PM, "Kanami" [email protected] wrote:

I've seen a "mouse pops out of window" sometimes in Minecraft, (also using
nvidia drivers).

Also, possibly related: TF2 displays a similar problem to Solar 2 in that
both tend to have weird handling of the mouse (where the mouse pointer is
pointing at one area of the window, but the window thinks I'm pointing at
another area), and problems getting the game to switch resolutions.

—
Reply to this email directly or view it on GitHubhttps://github.com/ValveSoftware/steam-for-linux/issues/1818#issuecomment-14188171
.

I finally found out it was just a hardware issue. It occurred for this mouse regardless of OS or computer it was used on, while other mice did not have the problem.

As I said I think this bug can be closed, unless anyone else has a use for it.

With the latest system updates this mouse issue is spreading. Now my mouse has major issues everywhere. Sometimes clicks are doubled, holding a mouse button seems to depress and then reengage suddenly, etc. It's some kind of kernel and/or driver interaction, for me.

Happens to me all the time with all games because I only play in windowed mode. Am running Ubuntu 14.04 x64. Running Win 7 Ultimate x64 on the same laptop I haven't observed this issue.

I'll just add that this is still occurring occasionally for me when I'm under a lot of lag. I still hold that it's the actual game client failing to hold the mouse as the lag increases.