I have always been able to copy a checklist and it unchecks the list automatically so I can start over but it's not doing that anymore. It will copy the checklist now but all the items are checked and I don't see an option for unchecking them all at once so I can start fresh.
I have the same problem, it's intensely annoying as my checklist has 30 items and I need to uncheck all checked items whenever I copy the card. Assuming this is a new "feature", the "workaround" for you could be to keep an unchecked template copy of that checklist that you can copy every time. For me that won't work since my checklist evolves while in use (I edit, resort or add/remove items frequently), and I don't want to have to do that on the template copy as well, but maybe it is enough for you.
Depending on how often you do this, you might find this uses up a lot of your quota. Here's a Trellinator command that would do the same thing -- you could install this globally which would mean that it would apply on every board where Trellinator was a member and would essentially reverse this feature change:
You can read more about Trellinator here:
If you had to thrive a new habit during a lockdown, what would it be? Trello
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