Description: When you open LibreOffice, when you open a new window, or when you use a menu bar, you will see that first a white context is created, and then it is changed into dark. That causes annoying white flash effect. Steps to Reproduce: 1. Make sure that dark mode is active on Windows. 2. Open LibreOffice and open a few windows (like "Tools > Options", etc. 3. Open a menu bar item and try moving the mouse between different menus. Actual Results: You may see a white window is created, and then it becomes dark, and then contents are added. The whole thing happens in relatively short time (depending on machine speed), but it is visible to the user. Expected Results: In dark mode, every window should be dark from the initial creation. Reproducible: Always User Profile Reset: No Additional Info: Version: 25.8.3.2 (X86_64) Build ID: 8ca8d55c161d602844f5428fa4b58097424e324e CPU threads: 20; OS: Windows 11 X86_64 (build 26200); UI render: Skia/Vulkan; VCL: win Locale: en-US (en_US); UI: en-US Calc: CL threaded
Created attachment 204754 [details] Screen record of white flash on Windows This is a screen record that shows white flash in: * LibreOffice startup * Tools > Options window creation * Selecting menus from menu bar and moving the mouse around
I guess Vulkan surface (or the way it is created) can be one source of this issue. Therefore, I copy the details here: RenderMethod: vulkan Vendor: 0x10de Device: 0x25a0 API: 1.4.312 Driver: 581.228.0 DeviceType: discrete DeviceName: NVIDIA GeForce RTX 3050 Ti Laptop GPU Denylisted: no It is worth noting that I don't see such a white flash with the demo dark mode win32 application in below project (requires Visual Studio build): Darkmodelib – Win32 Library for Dark Mode Support https://github.com/ozone10/darkmodelib Therefore, I think it can not be a driver and/or underlying win32 issue.
Confirmed, *very* brief flash before full draw in dark mode fo both skia/Vulkan and skia/Raster framing. But at this level of hw it is hard to consider it an annoyance. RenderMethod: vulkan Vendor: 0x10de Device: 0x2803 API: 1.4.312 Driver: 581.16.0 DeviceType: discrete DeviceName: NVIDIA GeForce RTX 4060 Ti Denylisted: no =-testing-= Version: 25.8.4.2 (X86_64) Build ID: 290daaa01b999472f0c7a3890eb6a550fd74c6df CPU threads: 28; OS: Windows 11 X86_64 (build 26200); UI render: Skia/Vulkan; VCL: win Locale: en-US (en_US); UI: en-US Calc: CL threaded Version: 25.8.4.2 (X86_64) Build ID: 290daaa01b999472f0c7a3890eb6a550fd74c6df CPU threads: 28; OS: Windows 11 X86_64 (build 26200); UI render: Skia/Raster; VCL: win Locale: en-US (en_US); UI: en-US Calc: CL threaded
(In reply to V Stuart Foote from comment #3) > Confirmed, *very* brief flash before full draw in dark mode fo both > skia/Vulkan and skia/Raster framing. But at this level of hw it is hard to > consider it an annoyance. Maybe not everyone is affected by white flashes, but it is considered harmful for some people. Please see: "Avoid flashing web content Overview Content that flashes repeatedly can be harmful to people with photo-sensitivity or seizure disorders like epilepsy. Flashing content can lead to reactions like vomiting and nausea, and trigger seizures if the flashes are severe enough." https://marcom.wwu.edu/accessibility/guide/avoid-flashing-web-content Also: "Three Flashes or Below Threshold (Level A) Individuals who have photosensitive seizure disorders can have a seizure triggered by content that flashes at certain frequencies for more than a few flashes. People are even more sensitive to red flashing than to other colors, so a special test is provided for saturated red flashing. These guidelines were originally based on guidelines for the broadcasting industry as adapted for desktop monitors, where content is viewed from a closer distance (using a larger angle of vision)." https://www.w3.org/WAI/WCAG22/Understanding/three-flashes-or-below-threshold.html There is also some pink flashes in Windows, in which I will file in another bug report.