To use the Hiddify-Linux-x64.AppImage on a Linux system (same for Cinnamon or KDE Desktop Environment), follow these simple steps to run it (without using a terminal):

1. Download the AppImage file: First, ensure you have downloaded the Hiddify-Linux-x64.AppImage file from the official Hiddify repository or website.

2. Open File Manager: Locate the downloaded file in your file manager (usually Nemo or another file manager).

3. Make the File Executable:

   • Right-click on the Hiddify-Linux-x64.AppImage file.
   • Select Properties.
   • Go to the Permissions tab.
   • Check the option Allow executing file as a program.

4. Run the AppImage:

   • Double-click on the Hiddify-Linux-x64.AppImage file to launch the application.

(These steps usually need to be done once, with each new .AppImage file that is downloaded)

Or steps to do it (with the use of a terminal):

1. Download the AppImage file: First, ensure you have downloaded the Hiddify-Linux-x64.AppImage file from the official Hiddify repository or website.

2. Make the AppImage Executable: Open your terminal and navigate to the directory where the AppImage file is located. Run the following command to make the file executable:

   chmod +x Hiddify-Linux-x64.AppImage

3. Run the AppImage: After making it executable, you can run the AppImage directly from the terminal with the following command:

   ./Hiddify-Linux-x64.AppImage

(These steps usually need to be done once, with each new .AppImage file that is downloaded)

The problem was solved perfectly, sincere thanks!