I just transferred 5 sats from my BlueWallet to my newly created Muun wallet. Cost was 1 sat, instantenous.

BlueWallet I think understand. It is custodial. But Muun wallet.... I thought it was non-custodial? Meaning I need to open a channel, i.e. do a on-chain transaction, before receiving fund via lightning?

This makes me confused. How is this possible in a non-custodial muun wallet?

I feel apprehensive about using Muun wallet. No clear distinction between Lightning balance and on chain balance. A bit too user friendly. For a non-material bearer asset like BTC (first time in human history), a bit more DIY is needed IMO.

Now, BlueWallet is also very user friendly. But they are upfront about being custodial, and also very clear distinction between lightning and onchain.

So what happens when the amount paid for a lightning invoice is not the same as the amount invoiced? Does the transaction go through or fail?

So I mined 0.00014167 BTC on NiceHash.

Now I am trying to withdraw the BTC to BlueWallet.

I created an invoice for 0.00014167 BTC using BlueWallet

But when I try to withdraw 0.00014167 BTC from NiceHash, it says there is a 0.00000002 BTC network fee.

So I am wondering if the BlueWallet invoice amount should be 0.00014167 BTC or 0.00014165 BTC?

So let's say I make a 2 of 3 multi-sig.
So I have a total of 3 seeds and 3 zpubs.

Am I correct to say that I require at least 2 seeds and 1 zpub to be able to access the coins?

So if I lose one seed and its associated zpub, then I will lose the coins?

So if three people have joint custody, the seed storage should be as follows?

Store seed    Store zpub
    1               2, 3
    2               1, 3
    3               1, 2

But when I move my BTC to a safe wallet, someone is going to mirror that transaction on Bitcoin Cash?
So isn't it an endless game of cat and mouse?

If I move my BTC to a SegWit address, then on BCH it will appear as a "anyone can spend" UTXO therefore immediately stolen?

So, Bitcoin Cash and Bitcoin both use the same address system?

I personally got into Bitcoin long after Segwit, so I have no BCH.

But let's say someone owns both BTC and BCH after the hard fork.

And then, he wants to sell BCH and buy BTC.

However, when he broadcasts a transaction on BCH, what is to stop someone from broadcasting the same transaction on the BTC network?

Worse, since Segwit essentially creates a "anyone can spend" UTXO as interpreted by pre-Segwit nodes, if he transfers BTC into a Segwit address, what is to prevent someone from stealing his coins on BCH?

This "anyone can spend" concept is interesting.

I read on Jimmy Song's blog that before Taproot is activated, if I transfer coins to a Taproot address, then anyone with or without the private key can just take those coins.

So.... let's say there's a bunch of people running non-mining full nodes that were installed in 2015 and never updated. They use this "anyone can spend" rule and publish transactions stealing coins from bc1q addresses.

A mining node running 2015 software mines a block containing those transactions. This block gets accepted by non-mining nodes running 2015 software, and rejected by non-mining nodes running 2018 software.

What happens? We get a hard fork?

Ok so if I download the Bitcoin software from 2015 and run it. Then I can basically steal all the coins from bc1q addresses. But the miners would refuse to include those transactions?

So let's say Taproot activates, but then majority of the non-mining nodes are too lazy to upgrade. And there still remain a sizeable number of miners who refuse to upgrade. Then a non-mining node publishes a transaction stealing Taproot coins using the "anyone can spend" rule. And this transaction gets mined by a mining node, and the block is accepted by non-upgraded non-mining nodes. We get a hard fork??

Ok, so people say that SegWit is a soft fork. What does this mean?

So let's say I was running a version of Bitcoin Core that was downloaded and installed 2 years before SegWit activation. And then I just left it running without updating the software.

And then on SegWit activation day, blocks start coming in that contain Segwit transactions, eg. those bc1q addresses. So my 2-years outdated Bitcoin Core will accept those blocks as entirely valid and then add those blocks to my local Block Chain?

So what is to prevent me from doing my own soft fork? Let's call my soft fork SegCash, and then I buy a bunch of mining equipment and start mining my own blocks. Will those blocks that follow my own soft fork rules be accepted by all the other nodes?

I also heard people saying that SegWit is actually a block size increase. Wait what? So you can do a soft fork to increase the block size, and Bitcoin Core clients which are 2-years outdated will accept those blocks as valid and add those blocks to their Block Chain?

Am I understanding this correctly? Before SegWit, the Block Chain increases by 1 MB per 10 minutes on average. After SegWit, the Block Chain increases by 1 to 2MB per 10 minutes on average?

So what is to prevent me from doing my own soft fork and increase the block size to 100MB per block? And then I buy a bunch of mining equipment and mine my own blocks which follow my own soft fork rules, and then those blocks will be accepted by the rest of the network?

So if a miner were to start mining TapRoot blocks right now, those blocks will also be accepted by the rest of the network as valid?

So I just downloaded Bitcoin Core.
But, when I ran the software, it says I have to download the entire 350GB blockchain.
This must be done whether I want to run a full node or a pruned node.

I want to ask: What happens in the event of a hard disk failure or a Windows reinstallation?
Do I have to go through the entire process of re-downloading and re-verifying the entire blockchain every time?
Or is there a way to download a pre-verified blockchain and just continue from whereever it left off?

I imagine that after setting up a full node with 350GB of data, I can just backup all the files.
And then if I reinstall Windows or my HDD fails, I can just restore the backup and then carry on from whichever block it was left off?
But if such a process can be done, then there must exist somewhere where I can downloaded a backed up version of a fully synced Bitcoin node, and then just carry on from there, without having to go through the tedious process of downloading and verifying from genesis myself?

Wow that is good news. I will want to run a pruned node.

However, when I first run Bitcoin Core / Bitcoin Knots, it only gives me two options. Both options require me to download the entire 350GB blockchain, regardless of whether I want to run a full node or a pruned node.

That triggers me a lot. Feels like the developers forcing me to do a lot of extra work.

And if I reinstall my computer or my harddisk fails, then I have to do everything all over again.

So I want to know if there is an implementation of Bitcoin where I can just start with a pruned node. I will sacrifice the security of verifying the entire chain from genesis for the convenience of just downloading what is necessary to construct a pruned node.

Ok, so currently the only two options for running a full node are Unpruned and Pruned.

Unpruned costs 350GB. Pruned requires trusting third parties for historical data.

I am proposing a "partially pruned" full node.

Basically, a Pruned full node plus all currently non-zero UTXO.

This can save disk space, plus not having to trust third parties for historical data.

The list of all non-zero UTXO can be constructed from an Unpruned full node. Or it can be downloaded from somewhere.

Do I have to start a new wallet in order to run Bitcoin core?
What if I just want to use Bitcoin core as a block explorer?
I don't want to type in my cold storage wallet data on any internet connected computer.

I just want to run a full node where I can just type in a certain public key, and it tells me which UTXOs are associated with this key. Basically a local version of blockchain.com/explorer

Furthermore I don't have the space to store 350GB of data.
As far as I can tell, if I run a pruned node, when I want to look up a certain public key I will have to reference other people's nodes. Basically a pruned node is no different from blockchain.com/explorer.

So I am think this:
If I can just store the complete set of all current UTXOs, plus the most recent 2016 blocks, then it is to all intents and purposes the same as running a 350GB full node.

I am trying to run Bitcoin core, but when I started the software, it says that I can either:

1) Download the entire blockchain and keep it on my disk, 350GB
2) Download the entire blockchain, verify historical data, and only keep the most recent 2 GB of blocks.

Either way, I have to download 350GB of historical data.

Forgive me, Toxic Maxis, but is there an implementation of Bitcoin Core where I can only download the most recent 2GB of blocks?

Furthermore, I have another idea.

Is it possible to build a full node that stores only the latest UTXO set and the latest 2016 blocks for difficulty adjustment?

If I store all current UTXOs and the latest 2016 blocks, is it to all intents and purposes, the same as storing the entire 350GB block chain?

If no such software exists I will build it from scratch. I am currently reading Programming Bitcoin by Jimmy Song.

I understand that there was a massive Bitcoin theft due to Android OS's SecureRandom function being not random enough.

I am concerned about Ian Coleman's tool having the same issue? Maybe not now, but in the future?

I plan to use Ian Coleman's HTML tool in Tails air gapped environment. Using a watch only wallet on my main PC and signing transations on an air gapped PC.

I was wondering if I should shake a dice 256 times to generate my own entropy? Would that be considered more random than Crypto.getRandomValues()?

Also I realized that the seed phrase can be more than 24 words long? 11 bits per word. So maybe use Crypto.getRandomValues() to generate 24 words, and then add another 12 words to it to get 36 words? Is this more secure or just overkill?

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By the way, how do you key in your 24 words into Trezor? Say you already have a seed phrase and buy a brand new Trezor. What do you do then? There are only 2 buttons on Trezor right?

Ok so basically whether you use Electrum, Trezor or Ledger, the piece of paper where you write down the seed phrase is the real "wallet" right?

How secure is the seed phrase generated by Ian Coleman's HTML tool? Assuming running on Tails without persistent storage, offline.

What is the random number generator used by Ian Coleman's HTML tool?

Do hardware wallets generate their seeds on the hardware dongle itself? What is the random number generators used by Trezor, Ledger etc?

Also I want to use a BIP 39 seed in Electrum. I don't like Electrum's usage of a "special" key derivation algorithm.

People always say "bitcoin has a hard coded, guaranteed limit of 21 million coins".

However, I think the limit of 21 million is subject to the consensus of the users and miners?

So if a consensus is formed to allow more than 21 million Bitcoins to be generated, then it will be so, right?

Actually everything in Bitcoin can be changed, as long as there is the consensus for it.

So, there is actually no mathematical limit to the number of coins. It's just that the issuance of coins is not subject to a central authority, but requires a supermajority consensus.