I've followed the procedures in your HOWTO for creating a subtheme.
https://www.drupal.org/node/2866181 →
It all works fine. However, since I had already customized my subtheme when it was named drupal8_w3css.subtheme, all customizations(colors primarily) were lost. No big deal, 5 minutes to recreate, but it might be worth a documentation note that any previous customization will be lost.
Conceptually, I take it that the purpose of the renaming is so that when you update versions, say 8.x-1.6 to 8.x-1.7 any files that you've updated in your customized subtheme will not be overwritten? However, I am just wondering if any "desirable" updates such as bug fixes or function enhancements will not automatically get carried through to the new renamed and customized subtheme? Or are these changes confined to the base theme?
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Fixed
1.6
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