show file path on custom theme tooltip

Modules/Settings/ThemeColorsTab.qml

@@ -528,11 +528,16 @@ Item {
                                 anchors.bottom: parent.top
                                 anchors.bottomMargin: Theme.spacingS
                                 anchors.horizontalCenter: parent.horizontalCenter
-                                visible: customMouseArea.containsMouse && (Theme.currentThemeName !== "custom")
+                                visible: customMouseArea.containsMouse
 
                                 StyledText {
                                     id: customTooltipText
-                                    text: "Load custom theme from JSON file"
+                                    text: {
+                                        if (Theme.currentThemeName === "custom")
+                                            return SettingsData.customThemeFile || "Custom theme loaded"
+                                        else
+                                            return "Load custom theme from JSON file"
+                                    }
                                     font.pixelSize: Theme.fontSizeSmall
                                     color: Theme.surfaceText
                                     anchors.centerIn: parent

docs/CUSTOM_THEMES.md

@@ -55,7 +55,17 @@ These are the essential colors that define your theme's appearance:
 }
 ```
 
-You can the colors at the top level if you do not want "dark" and "light" variants.
+You can define colors at the top level if you do not want "dark" and "light" variants.
+
+For example:
+
+```json
+{
+  "name": "Theme name",
+  "primary": "#eeeeee",
+  ....
+}
+```
 
 ## Example Themes