This plugin used to select by regex. Command Select By Regex: All selects all, Select By Regex: Next selects first found regex for each selection. If you want restrict search for line, use Expand Selection to Line before calling Select By Regex command.
If regex contain groups, then groups will be select. To exclude group from selection use (?:...) group. Select By Regex: Next can also use $_ to match string under current selection.

You can run Next command while it is active to go through matches:

You can use this keymap

{
    "keys": ["alt+shift+/"],
    "command": "select_by_regex_all",
},
{
    "keys": ["alt+/"],
    "command": "select_by_regex_next"
}