ui: Enable multi viewports on Linux again if you're not on Wayland

lib/libimhex/include/hex/helpers/utils.hpp

@@ -291,6 +291,8 @@ namespace hex {
 
     bool isProcessElevated();
 
+    std::optional<std::string> getEnvironmentVariable(const std::string &env);
+
     namespace scope_guard {
 
 #define SCOPE_GUARD   ::hex::scope_guard::ScopeGuardOnExit() + [&]()

lib/libimhex/source/helpers/utils.cpp

@@ -451,4 +451,13 @@ namespace hex {
 #endif
     }
 
+    std::optional<std::string> getEnvironmentVariable(const std::string &env) {
+        auto value = std::getenv(env.c_str());
+
+        if (value == nullptr)
+            return std::nullopt;
+        else
+            return value;
+    }
+
 }

main/source/window/window.cpp

@@ -41,6 +41,7 @@
 #include "init/tasks.hpp"
 
 #include <GLFW/glfw3.h>
+#include <GLFW/glfw3native.h>
 
 #include <nlohmann/json.hpp>
 
@@ -650,9 +651,12 @@ namespace hex {
         style.WindowRounding = 0.0F;
 
         io.ConfigFlags |= ImGuiConfigFlags_DockingEnable | ImGuiConfigFlags_NavEnableKeyboard;
-#if !defined(OS_LINUX)
+
+        {
+            auto sessionType = hex::getEnvironmentVariable("XDG_SESSION_TYPE");
+            if (!sessionType || !hex::containsIgnoreCase(*sessionType, "wayland"))
                 io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;
-#endif
+        }
 
         for (auto &entry : fonts->ConfigData)
             io.Fonts->ConfigData.push_back(entry);