Separate a group of tags, then placing them on a select component

Shopify Discussion
1

have a large set of tags, and I want to be able to sepparate them. For example, I have the Green, Blue, Red, Black, Colorless and White tags (as well as some other tags that aren’t colors, so I won’t put them here) and I want to place them in an array. I tried with something like this:

{% assign colors = "" | split: '' %}
{% for tag in collection.all_tags %}
    {% if tag == 'Black' or tag == 'Blue' or tag == 'Colorless' or tag == 'Red' or tag == 'White' %}
        {% assign comma = "," %}
        {% assign color = tag | split: '_' %}
        {% assign colors = colors | concat: color %}
        {% assign colors = colors | concat: comma %}
    {% endif %}
{% endfor %}

However, that returns me “BlackBlueGreenRedColorlessWhite”, without any spaces whatsoever. Also, is there a way I can place those selected tags in a select component so I can filter my products by the selected tag? Like in the example provided in this page but using a select instead of a ul