In IE, if you have a style-sheet updated to certain component (server component) and if they are inside update panel when a ajax post back happens you might loose the style-sheet.
I faced this problem while working on a small user control which is like toolbar. I have created that with LinkButton controls and when i placed this user control inside update-panel after click on the link entire style sheet goes off from the link button.
This bug was reported way back in 2006 and it happens only in IE. It seems like MS is not interested to fix this but either in Atlas or in IE and has closed this issue by calling it an Behaviour By Design.
There is a way around to fix this issue. I have added following code in OnInit Event of my user control and i got styles retained on link button.
protected override void OnInit(EventArgs e)
ScriptManager sm = ScriptManager.GetCurrent(Page);
string css = """;
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