Using the Snap
The Snap runs inside a protected sandbox ("strict confinement"). That keeps your system safe, and it means a few things work a little differently from the APT and Fedora packages.
What works with no setup#
- Printing, through the printing connection that comes with the Snap Store install.
- Reading and saving files in your home folder (including Documents, Downloads, and Desktop).
- Opening files you choose in the file chooser, wherever they are.
- The system theme, dark mode, and your system language.
To see what is connected, run snap connections thermalprint.
If printing is not connected#
Normally the printing connection happens automatically. If it did not (for example, with a package you installed by hand), ThermalPrint tells you in the status bar and in Print Center, with the exact command:
sudo snap connect thermalprint:cups cups:cupsIf the cups Snap is missing, install it first with sudo snap install cups.
Saving to USB drives and other disks#
The Snap cannot see removable drives until you allow it. This is optional and only needed if you want to save or open files on external storage directly:
sudo snap connect thermalprint:removable-mediaSaved designs and double-click opening#
A Snap cannot register a new file type with your desktop. If you only have the Snap installed (no APT or Fedora package), run this once from a normal terminal, not from inside the Snap, to make .thermalprint files open in ThermalPrint when you double-click them:
/snap/thermalprint/current/usr/share/doc/thermalprint/register-mime.shThe helper also copies the file icon into your user icon folders, including the folder of your current icon theme, so themes such as Zorin show it. Restart your file manager afterward (nautilus -q). A Snap cannot install a preview thumbnailer, so Snap-only installs show the icon, not a picture of the label. It claims only .thermalprint files, never PDFs, images, or other JSON files. It needs shared-mime-info and xdg-utils, which most desktops already have. The script refuses to run if started inside the Snap.
Folders and the watch folder#
| Folder | Works in the Snap? |
|---|---|
| Your home folder and normal subfolders (Downloads, Documents) | Yes. |
| A folder chosen in the file chooser | Yes. |
Hidden folders (those starting with a dot, such as ~/.cache) | No. The Snap cannot read them. |
Other disks, /media, /mnt | Only after removable-media is connected. |
When you choose a folder the Snap cannot read, the Watch a folder section shows a hint explaining why, and watching stays off.
Opening this manual and web links#
The Help button opens the manual in your default web browser. This uses the Snap's network permission only to hand the link to your browser; ThermalPrint does not download anything itself.
Where the Snap keeps your data#
Preferences, printer profiles, print history, and your own templates, logos, fonts, and address book are stored in the Snap's own folder, so they do not mix with the data of a non-Snap installation. Settings made in a non-Snap installation are not copied. See Settings and privacy for the paths.
Snap channels#
The Store version tracks the stable channel and updates itself in the background. To go back to a previous version, run sudo snap revert thermalprint.