Segwit and Segwitx2

[G3nijalac]

Hello I am trying to understand if Electrum versions prior to all this Segwit and Segwitx2 implementation (2.7.x 2.8.x 2.9.x for example)
are all still functional wallets?
I.e. are they still able to send and recieve bitcoins to and from any BTC addresses? including Segwit and non Segwit ones?

[xdrpx]

Segwit2x was never implemented, it was later shutdown by a few people who supported it.

Now for Segwit support Electrum 3.0 brings Segwit Bech32 address support and you'll be able to send funds using it to other segwit and nonsegwit addresses but you'll not be able to  receive funds in it from non-segwit addresses. This is because many exchanges and wallets are yet to add support for Segwit and it's slowly happening. Electrum was quick to provide support and it's a good place to start (With version 3.0). Thus to receive funds you'll need to probably have another non-segwit / legacy wallet which you can do so even in version 3.0 or older version of electrum. Hence all the older electrum wallets are still functional wallets that can send bitcoins to non-segwit addresses and receive bitcoins from any addresses.

[G3nijalac]

So if I understood correctly

by using an older version I will have no problems reciveing funds from any address (non Segwit and Segwit)
but I would not be able to send to a Segwit address?

and by updating to a newer version I would be able to send to Segwit and non Segwit
but I would not be able to recieve btc from non Segwit addresses?

so both choices have major drawbacks and I have to choose from either having to research if the address Im sending too is Segwit or non Segwit
or doing the same when reciveing btc (making a withdraw from some site or exchange)

The way I see it is that making any sort of outgoing or incoming trx right now is risky untill everybody switches to Segwit?

What would happen if i try to pay an invoice to BitPay for example from an older version?
the TRX would not get confirmed? my coins would be lost? or return to my balance?

What is the best longterm solution to avoid any issues or risks?

[xdrpx]

You shouldn't worry much as long as you wait for segwit support to be implemented accross multiple wallet platforms and exchanges. (Coinbase is soon to implement it and Bitcoin core already has it in a way where you can generate segwit addresses from console).

Let me try to explain a bit about Electrum 3.0's implementation of segwit addresses and about the current wallet market segwit adoption scenario:

1)  BC1 (Bech32 address) is a native segwit address following BIP173. So if you create a native segwit address in electrum which is the default segwit address, then you'll be fine. So what all you can do with this?

a) You'll be able to receive from other BC1 (Bech 32) segwit address (At the time of me writing this, only electrum supports this, many other wallets will soon follow suite) by people who have a wallet that supports it. So it means another electrum 3.0 segwit wallet user can send money to you and you will receive it fine.

b) You can send money to any kind of wallet, may it be native segwit, segwit-p2sh wallet (segwit addresses starting with '3') and old addresses starting with '1'

2) Segwit-p2sh wallet (addresses starting with '3'). Although addresses starting with 3 have been existing from the time Bitcoin was created in the form of multi-sig wallets, the same kind of addresses are present for segwit-p2sh wallet's. These are backward compatible with older addresses. With such segwit wallets you can send bitcoin to any old address and segwit-p2sh address and receive from the same. Now, about sending and receiving to and from BC1, again wallets need to support this which will soon be added by many wallets over time.

3) Now about old electrum wallets (2.9) and below and even electrum 3.0 (this is when you create a wallet in 3.0 with old wallet option instead of segwit), you'll always have old addresses or multi-sig addresses with these wallets, but no segwit addresses. I would recommend that until SegWit becomes mainstream and more wallet softwares support it (if they support it, then more people will start using segwit and reap the benefit of very low fees) you should probably utilize a old address or atleast a segwit-p2sh address if needed. There's no risk and you can perform transactions safely.

If you pay an invoice to bitpay from an older electrum version (2.9) and below without segwit address, you'll be fine as your old addresses don't become obsolete, because if it does then people would not be able to use their funds. They'll get confirmed on the blockchain. SegWit is backwards compatible and will eventually allow sending from and through old, Segwit-p2sh and Native Segwit addresses as wallets implement it.

[G3nijalac]

xdrpx thank you very much for taking the time to explain it to me :-)

so even if BitPay generates a Segwit address for the invoice I can still pay it from an old electrum version.. correct?

is there any tool for detecting if an addy I want to send to is Segwit or non Segwit?

[BitMaxz]

xdrpx thank you very much for taking the time to explain it to me :-)

so even if BitPay generates a Segwit address for the invoice I can still pay it from an old electrum version.. correct?

is there any tool for detecting if an addy I want to send to is Segwit or non Segwit?

I don't see any checker yet for bitcoin to check if its segwit or non segwit support..
But you can notice the bitcoin address if segwit support the address would start with "bc1" (bech32 addresses for segwit)
But there are  bitcoin addresses segwit supported that start from "3" but not all addresses are segwit supported..

And i think it will not be a problem if you send bitcoin in bitpay.. never had a problem with bitpay when buying something in online and use the bitpay as alternative payment processor..

[Iranus]

so even if BitPay generates a Segwit address for the invoice I can still pay it from an old electrum version.. correct?

Yep.  It's no different for you to send to a SegWit address as it would be for you to send to a legacy address.

is there any tool for detecting if an addy I want to send to is Segwit or non Segwit?

No, but P2SH (Pay to Script Hash) addresses begin with a 3.

If the address begins with a 1, it's definitely a legacy address, and if it starts with a 3, it's either a SegWit address or it's using one of the other uses of P2SH addresses (namely multisig).