Flatpak Caveats
Sleek can be installed as a Flatpak via Flathub on Linux. As Flatpaks are running in a sandbox, sleek's permissions to do things are limited. See Flatpak's Sandbox Permissions docs.
When you open a todo.txt file via file chooser or drag-and-drop, Flatpak creates a temporary link for that file. Sleek won't know the real path of the file, rather it'll look something like this: /run/user/1000/doc/8b60c039/todo.txt. When you're restarting sleek, you now may receive an error as sleek tries to open that file again. That error could look like this: Error: ENOENT: no such file or directory
This is because sleek now doesn't have the permission any more to open that file you had opened previously. Luckily, there's a fix for that by giving sleek the permission to access specific file paths on your filesystem. Do this for all the files you want to regularly access with sleek, including archive files (done.txt).
You can give sleek permission to always access your files by running flatpak override like this:
flatpak override --user com.github.ransome1.sleek --filesystem="/path/to/todo.txt"
flatpak override --user com.github.ransome1.sleek --filesystem="/path/to/done.txt"
Flatseal is a handy graphical app to manage Flatpak sandbox permissions. Search for sleek in the list, scroll down to the filesystem section and add the file paths to the "Other files" option.
