Icon not added by "AppImage Launcher"

Hello, I have the same issue here in Ubuntu 20. When I "Integrate and Run" the AppImage with AppImageLauncher, the MU icon appears in the side bar, but in the Applications desktop menu, MuseScore 3.6-portable has the default system "gear" icon. When I close the first run of the application and re-open it from the desktop menu shortcut, Musescore uses the gear icon in the side bar. ~/.local/share/icons/hicolor/{size}/apps/ also does not contain the MuseScore icon for any of the sizes. Can you help me with this?

Generally, we have no control over how third-party utilities like "AppImage Launcher" work, and indeed, often they don't. I recommend installing the AppImage the supported way we provide ourselves and document in the installation instructions: simply run the AppImage with the "install" option. This should do the necessary integrations.

However, on some systems, there can be a problem due to a mismatch between the application name in the desktop file and the name the application actually runs as. I find on my Debian-based system, I need to edit the desktop file to change the application name from "MuseScore 3.6.2 Portable AppImage" to simply "MuseScore 3", then the icon works. Maybe a similar fix would help with the AppImage Launcher too, but I don't know anything about how that works. I know with the regular support install option, the desktop file goes to ~/.local/share/applications and you edit it there.

OK, it's still not clear if this is a bug on the "AppImage Launcher" program or a side effect of the discrepancy in the naming, but anyhow, it's definitely something we'd like to work better for all systems in the future.

Could simply be an unwarranted assumption made by that third party installer program - something that happens to be true for some AppImages but not necessarily all. Which again is why we recommend using the "install" we provide and support ourselves - but as mentioned, on some systems at least, you still need to customize the desktop file to set the application name to "MuseScore 3".

I'll comment here, beyond just "I'm also experiencing this issue".

I decided to try the MuseScore AppImage after an Ubuntu 20.04.3 LTS update made the MuseScore snap unusable.

According to https://appimage.org/, the story is:

> Download an application, make it executable, and run! No need to install.

and:

> To run an AppImage, simply:
> - Make it executable
> $ chmod a+x Subsurface.AppImage
> - and run!
> $ ./Subsurface.AppImage
> That was easy, wasn't it?

The implication, from that marketing copy, is that everything the app needs to run should be contained in the AppImage and should not need to be "installed".

Since I don't knowing the technical details of AppImages, how they're built, or what the software contract for them is, I myself would be cautious about making "unwarranted assumptions" in either direction. However, one thing I do know in the world of software is that one person's unwarranted assumption is another person's poorly documented contract.

That said, part of the whole story for AppImages is to enable ease of distribution, ease of use, ease of update/removal, etc. Third-party tools like AppImageLauncher exist because they fill gaps in that process in predictable and automated ways, rather than a random install argument to an AppImage that is supposed to "just work".

(Note that I'm not sure how I would have discovered the magic install argument to the MuseScore AppImage if I had not experienced this icon problem myself and happened to find this forum discussion, as I never would have known to look for such an argument to an AppImage. Is there an equivalent "uninstall" to remove the detritus later on?).

How about we all work together and figure out why some AppImages such as KeePassXC work fine without installing, and MuseScore has difficulty with that? Is this a limitation in the AppImage format? (Note that I picked KeePassXC as an example because it, like MuseScore, also uses Qt5). How can the community help MuseScore improve this?

I think I have encountered a relative of this problem. Installed the latest appimage (3.6.2.5) on Ubuntu 22.04 using its own 'install' option. Runs perfectly and the icon appears in the side-bar. However the .mscz files do not have an associated icon. They do run musescore with a double click. Any hints how to associate an icon with the .mscz file type?

See my comment above - https://musescore.org/en/node/316255#comment-1082786. You need to edit the desktop file (in either /usr/local/share/applications or ~/.local/share/applications) to change the "Name" to "MuseScore 3" in order for most window managers to do the correct file associations and pick up the correct icon.

Thanks, Marc for prompt reply. I modified the .desktop file, first in the local and then in the global applications folder, rebooting after each attempt. Unfortunately it has not solved the problem.

As far as I know, that much is handled by your specific window manager, so you'd have to ask on a support forum for that to learn more about how those icons are chosen. Probably something involving MIME.

I was able to get the icon while using AppImage Launcher
1. Integrate the MuseScore appimage using AppImage Launcher
2. Edit the appimage desktop file, usually found in ~/.local/share/applications
3. Example: sudo gedit appimagekit_518417ed5e2cbbfaee303f73088a6268-MuseScore_4.2_Portable.desktop
4. Edit the value in "Icon=" to Icon=application-x-musescore4portable
5. Log out and log back in

Icon is now showing !