linux: workaround for wailsapp#2977

In NewWindow, set options.Linux.WebviewGpuPolicy to WebviewGpuPolicyNever
if options.Linux is nil, disabling GPU acceleration by default on linux
until the upstream bugs https://bugs.webkit.org/show_bug.cgi?id=228268
and https://bugs.webkit.org/show_bug.cgi?id=261874 are fixed.

v2/internal/frontend/desktop/linux/window.go

@@ -25,6 +25,7 @@ import (
 	"github.com/wailsapp/wails/v2/internal/frontend"
 	"github.com/wailsapp/wails/v2/pkg/menu"
 	"github.com/wailsapp/wails/v2/pkg/options"
+	"github.com/wailsapp/wails/v2/pkg/options/linux"
 )
 
 func gtkBool(input bool) C.gboolean {
@@ -90,6 +91,8 @@ func NewWindow(appoptions *options.App, debug bool, devtoolsEnabled bool) *Windo
 	var webviewGpuPolicy int
 	if appoptions.Linux != nil {
 		webviewGpuPolicy = int(appoptions.Linux.WebviewGpuPolicy)
+	} else {
+		webviewGpuPolicy = int(linux.WebviewGpuPolicyNever)
 	}
 
 	webview := C.SetupWebview(

v2/pkg/options/linux/linux.go

@@ -28,6 +28,11 @@ type Options struct {
 	//   - WebviewGpuPolicyAlways
 	//   - WebviewGpuPolicyOnDemand
 	//   - WebviewGpuPolicyNever
+	//
+	// Due to https://github.com/wailsapp/wails/issues/2977, if options.Linux is nil
+	// in the call to wails.Run(), WebviewGpuPolicy is set by default to WebviewGpuPolicyNever.
+	// Client code may override this behavior by passing a non-nil Options and set
+	// WebviewGpuPolicy as needed.
 	WebviewGpuPolicy WebviewGpuPolicy
 
 	// ProgramName is used to set the program's name for the window manager via GTK's g_set_prgname().