What is the ruling on growing the mustache while lengthening its sides (sabalin) and trimming what exceeds and hangs over the lips, and is trimming the beard forbidden?

The answer to this question was previously provided in fatwa: 131451 titled: "The Prophet’s Guidance (PBUH) Regarding the Moustache," and fatwa: 145576 titled: "How to Trim the Moustache, and the Ruling on Leaving its Sides." For details on the ruling of trimming the beard, please refer to fatwa: 73062.