The second most important way to support Bitcoin Core contributors is to donate to support their work.
The first most important way to support Bitcoin Core contributors is to review and test their wo...
More than that. I have it first hand that at least some core contributors aren't happy about donations because of the impact that has on the incentives. Learned a lot from a discussion I had while trying to give €50 worth of sats to a dev, and he was reluctant to take it. Many implications one doesn't normally think about
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