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Thanks for taking the time to make the PR @mradkov.
It looks correct to me and this fix of the doc will likely help many who are still omitting --chain alex.

Any reason not to use the images parity/polkadot:latest or say parity/polkadot:0.3.14-2a5e8fc ?

Any reason not to use the images parity/polkadot:latest or say parity/polkadot:0.3.14-2a5e8fc ?

I haven't changed this, to be consistent with what was documented in the file.

Maybe @chevdor can tell if there is any difference between the two.

Any reason not to use the images parity/polkadot:latest or say parity/polkadot:0.3.14-2a5e8fc ?

yes, because initially, there were no such images.
I wrote the initial doc along with the chevdor/polkadot image that I still maintain.

I am however not using the parity image so I have no clue if it works with the doc we currently have.

IMO, switching the container source belongs to another PR.
Here @mradkov is updating so users can still use the image with the latest changes.

@ddorgan merge when ready.