/mark in order to mark XYZ coordinates of specified blocks

In order to help many builders and those that use commands in order to fill or setblock certain items, I find that it would be beneficial to add a /mark command when looking at a specified block. Upon performing /mark, the XYZ coordinates of this block will be saved within a single link, which can then be clicked when performing other commands to copy and paste the information into the current cursors location. This can be used multiple times, with each command used on different coordinates changing the link to read Mark1, Mark2, Mark3, and so on.

To view all currently taken mark slots, /marklist will paste all marked blocks coordinates back into chat. In order to reset all currently used marks, /markreset would clear all mark blocks coordinates.

This saves a lot of time, as those that build with fill commands and setblock commands would no longer have to type XYZ coordinates out into non-command chat while look at the Debug Screen (F3), though this also helps with other commands that need a specific set of one or more block coordinates in order to perform actions.