Unity3d editor: how to prevent changes from being undone upon exiting play mode?
<p>Apparently this is some beginner's question (and that I am) but it's driving me crazy and I couldn't find any mention:</p>

<p><em>I Occasionally forget to exit <strong>Play mode</strong> and go on building my UI making objects and changes, only to realize that I'm still in <strong>Play Mode</strong> and as soon as I unpress the play button, these will be purged!</em> I suppose the <strong>Unity Editor</strong> has its reasons for allowing editing of Scripts/Scenes while in <strong>Play Mode</strong> (would be happy to hear some examples-maybe testing scenes?) but my main question here is:</p>

<p>Is there some way for me to prevent this behavior? Or at least some trick that you use to prevent <strong>me</strong> from making changes while in <strong>play mode</strong>? (Other than becoming paranoid about it and checking constantly...)</p>

<p>Thank you</p>

<p>PS. <em>sigh</em> time to head back to Unity and rebuild that UI that I lost...</p>