updates to flatpak installer

desktop/package/README.md

@@ -8,11 +8,12 @@ Follow these instructions to create installers for the Haveno Java desktop appli
 From x86_64 machine:
 
 1. `sudo apt-get update`
-2. `sudo apt install -y rpm fuse flatpak flatpak-builder`
-1. `./gradlew clean build --refresh-keys --refresh-dependencies` (or `make clean && skip-tests` after refreshed)
-2. `./gradlew packageInstallers`
-3. Confirm prompts.
-4. Path to installer is printed at the end. Execute to install, e.g.: `sudo dpkg -i <path>.deb` or open `<path>.deb` with Software Install.
+2. `sudo apt install -y rpm libfuse2 flatpak flatpak-builder appstream`
+3. `flatpak remote-add --if-not-exists --user flathub https://dl.flathub.org/repo/flathub.flatpakrepo`
+4. `./gradlew clean build --refresh-keys --refresh-dependencies` (or `make clean && skip-tests` after refreshed)
+5. `./gradlew packageInstallers`
+6. Confirm prompts.
+7. Path to installer is printed at the end. Execute to install, e.g.: `sudo dpkg -i <path>.deb` or open `<path>.deb` with Software Install.
 
 Note: Please see [flatpak.md](../../docs/flatpak.md) for information on
 distributing Haveno via Flatpak.

desktop/package/linux/exchange.haveno.Haveno.metainfo.xml

@@ -44,7 +44,7 @@
   </description>
   <screenshots>
     <screenshot type="default">
-      <image>https://files.catbox.moe/8pahgg.png</image>
+      <image>https://github.com/haveno-dex/haveno/blob/master/desktop/package/linux/preview.png</image>
       <caption>Recent Trades page</caption>
     </screenshot>
   </screenshots>

desktop/package/package.gradle

@@ -415,7 +415,8 @@ task packageInstallers {
             } else {
                 throw new GradleException("DEFAULT_APP_NAME not found in HavenoExecutable.java")
             }
-            // copy the manifest to a new tmp one in the same place
+
+            // Copy the manifest to a new tmp one in the same place
             // and add a --filesystem=.local/share/${name} to the flatpak manifest
             def manifest = file(flatpakManifestFile)
             def newManifest = file('exchange.haveno.Haveno.yaml')