--- a/dom/canvas/WebGLExtensionSRGB.cpp
+++ b/dom/canvas/WebGLExtensionSRGB.cpp
@@ -25,17 +25,17 @@ WebGLExtensionSRGB::WebGLExtensionSRGB(W
         gl->fEnable(LOCAL_GL_FRAMEBUFFER_SRGB_EXT);
     }
 
     auto& fua = webgl->mFormatUsage;
 
     const auto fnAdd = [&fua, gl](webgl::EffectiveFormat effFormat, GLenum format,
                                   GLenum desktopUnpackFormat)
     {
-        auto usage = fua->EditUsage(webgl::EffectiveFormat::SRGB8);
+        auto usage = fua->EditUsage(effFormat);
         usage->isFilterable = true;
 
         webgl::DriverUnpackInfo dui = {format, format, LOCAL_GL_UNSIGNED_BYTE};
         const auto pi = dui.ToPacking();
 
         if (!gl->IsGLES())
             dui.unpackFormat = desktopUnpackFormat;