Handle RPC_E_CANTCALLOUT_ININPUTSYNCCALL in OfficeViewer resize

[Copilot]

COM preview handlers throw 0x8001010D (RPC_E_CANTCALLOUT_ININPUTSYNCCALL) when SetRect is called during input-synchronous callbacks. This manifests as unhandled exceptions when resizing XLSX/CSV previews.

Changes

• Wrap SetRect call in PreviewHandlerHost.OnResize with try-catch for HResult 0x8001010D
• Exception is safely ignored as subsequent resize events will succeed

protected override void OnResize(EventArgs e)
{
    base.OnResize(e);

    try
    {
        var r = ClientRectangle;
        _mCurrentPreviewHandler?.SetRect(ref r);
    }
    catch (COMException ex) when (ex.HResult == unchecked((int)0x8001010D))
    {
        // Transient COM threading issue - next resize will succeed
    }
}

Original prompt

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This section details on the original issue you should resolve

<issue_title>Unhandled Exception with XLSX and CSV files</issue_title>
<issue_description>Describe the bug
I have multiple XLSX and CSV documents saved on my Desktop. Twice this evening, I have received exceptions when QuickLooking the files.

To Reproduce
Steps to reproduce the behavior:

1. Navigate to an XLSX or CSV file.
2. Press the Space Bar to activate QuickLook
3. The preview is shown, but an unhandled exception report is generated.

Expected behavior
The preview is shown, and there is no unhandled exception.

Desktop (please complete the following information):

• OS Version: Windows 11 Pro 25H2 (26200.7462)
• QuickLook Version: 4.3.0 from Github

Screenshots and Exception Log

************** Exception Text **************
System.Runtime.InteropServices.COMException (0x8001010D): An outgoing call cannot be made since the application is dispatching an input-synchronous call. (Exception from HRESULT: 0x8001010D (RPC_E_CANTCALLOUT_ININPUTSYNCCALL))
   at QuickLook.Plugin.OfficeViewer.IPreviewHandler.SetRect(Rectangle& rect)
   at QuickLook.Plugin.OfficeViewer.PreviewHandlerHost.OnResize(EventArgs e)
   at System.Windows.Forms.Control.OnSizeChanged(EventArgs e)
   at System.Windows.Forms.Control.UpdateBounds(Int32 x, Int32 y, Int32 width, Int32 height, Int32 clientWidth, Int32 clientHeight)
   at System.Windows.Forms.Control.UpdateBounds()
   at System.Windows.Forms.Control.WmWindowPosChanged(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

QuickLook.Exception.log

</issue_description>

<agent_instructions>************** Exception Text **************
System.Runtime.InteropServices.COMException (0x8001010D): An outgoing call cannot be made since the application is dispatching an input-synchronous call. (Exception from HRESULT: 0x8001010D (RPC_E_CANTCALLOUT_ININPUTSYNCCALL))
at QuickLook.Plugin.OfficeViewer.IPreviewHandler.SetRect(Rectangle& rect)
at QuickLook.Plugin.OfficeViewer.PreviewHandlerHost.OnResize(EventArgs e)
at System.Windows.Forms.Control.OnSizeChanged(EventArgs e)
at System.Windows.Forms.Control.UpdateBounds(Int32 x, Int32 y, Int32 width, Int32 height, Int32 clientWidth, Int32 clientHeight)
at System.Windows.Forms.Control.UpdateBounds()
at System.Windows.Forms.Control.WmWindowPosChanged(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Unhandled Exception with XLSX and CSV files #1854

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Pull request overview

This PR fixes an unhandled COM exception that occurs when resizing XLSX and CSV file previews. The exception RPC_E_CANTCALLOUT_ININPUTSYNCCALL (0x8001010D) is thrown when SetRect is called on preview handlers during input-synchronous callbacks.

Changes:

• Added try-catch block around SetRect call in OnResize method to handle transient COM threading exception
• Exception is safely ignored as subsequent resize events will successfully update the preview handler

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