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ASP.NET Modal Popup Extender displaying differently in same Firefox in diffferent PCs

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  • 4 have this problem
  • 11 views
  • Last reply by Vivek

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I developed a classic ASP.NET Web Forms application. In this application I use a Modal Popup Extender an ASP.NET AJAx component.

The component is correctly displayed in all the major browsers (IE, Firefox and Chrome) but today something strange happened.

In my computer the background of the Popup is grey (as it is supposed to be) but in some other computer with Firefox it is displayed white. All the computers use Windows 7.

I guess it is a matter of CSS but I still do not understand why Firefox interpret the CSS differently in different computers, when this must not be the case. Anybody knows why?

For completeness I attach the CSS code related to the Modal Popup Extender with class modalBackground

.modalBackground { background-color: Black; filter: alpha(opacity=80); opacity: 0.8; z-index: 10000; }

I developed a classic ASP.NET Web Forms application. In this application I use a Modal Popup Extender an ASP.NET AJAx component. The component is correctly displayed in all the major browsers (IE, Firefox and Chrome) but today something strange happened. In my computer the background of the Popup is grey (as it is supposed to be) but in some other computer with Firefox it is displayed white. All the computers use Windows 7. I guess it is a matter of CSS but I still do not understand why Firefox interpret the CSS differently in different computers, when this must not be the case. Anybody knows why? For completeness I attach the CSS code related to the Modal Popup Extender with class modalBackground .modalBackground { background-color: Black; filter: alpha(opacity=80); opacity: 0.8; z-index: 10000; }

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Hi,

You can try to deselect Use hardware acceleration when available in Firefox Tools (Alt + T) > Options > Advanced > General. If the problem persists please also check in a new profile. This would ensure a uniform setting. A new profile would have the default Firefox settings (Tools (Alt + T) > Options, and about:config ), and usually would also be empty of any Extensions and themes (Appearance) in Tools > Add-ons) and their settings. Also, a new profile would have no previous stored website data/settings etc., (Tools > Clear Recent History).

Profiles Howto

Profile Folder & Files

about:config Entries