Fixing Logitech Master 3S printing key with Linux with solaar

I ran into the same on Fedora. First make sure you have Solaar installed.

• Then, in Solaar, select the keyboard in the left column.

• In the right column, click the padlock icon for Key/Button Diversion until it is unlocked.

• In the dropdown, select Screenshot and change Regular to Diverted.
• Click the padlock icon to lock it again.
• Click the Rule Editor button in the lower right of Solaar.
• Under User-defined rules, right-click to insert a new rule.
• Right-click the new rule, and select Condition -> Key
• Specify Screenshot as the key, keeping Key down selected.
• Right-click again, and Insert below -> Action -> Key press
• Specify Print as they key

Make sure that the Key press action is after / below the Screenshot (pressed) condition, and save the changes.

This maps the Screenshot key (F7 on my MX Mechanical) to the Print Screen button, and that in turn fires the Ubuntu screenshot tool.

I have noticed that by default, that button emulates a left-shift + opt / start + s key combination, which doesn’t do anything on Ubuntu 22.04.