Since performing a jailbreak we do not violate the laws of our country (for example, in the United States jailbreaking is allowed), we have all the rights to it. Performing a jailbreak, the iPhone does not lose the warranty and is the same device as without a jailbreak.
Is Jailbreaking illegal? - No. Jailbreak is legal. If, after performing a jailbreak, you decide to turn in an iPhone for repair, Apple may not accept your iPhone. In this case, you have 2 ways - to demand to take an iPhone for warranty repair, since Apple has to fulfill it. The second way - before going to Apple, we recommend to remove the jailbreak from your iPhone and you will not be asked extra questions when taking it for repair.
Command (⌘) + Shift (⇧) + 3 - a screenshot of the entire desktop. If you have multiple monitors, the same number of files will appear.
Command (⌘) + Shift (⇧) + 4 - a screenshot of the selected part of the display. The arrow cursor turns into a sight with the current coordinates. You just have to choose the area of interest.
Command (⌘) + Shift (⇧) + 5 - opens the program Screenshot (only on macOS Mojave).
All these combinations can also be used with the Ctrl key. In this case, instead of saving to the desktop, the image will be immediately saved to the clipboard.
If you are going to publish screenshots somewhere in a blog or forum, it is better to optimize their size before posting. So they will load faster.
How to check macos version:
Tab + "About This Mac" = You. can see your macOS Version