Is this even POSSIBLE?

From	linux_forum1 <linux_forum1@protonmail.com>
Newsgroups	linux.debian.maint.firewall
Subject	Is this even POSSIBLE?
Date	2022-01-06 19:00 +0100
Message-ID	<DCFdn-2RA-1@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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Hello, I have 2 questions if that's OK.

INPUT DROP
FORWARD DROP
OUTPUT DROP

-N Block
-N Logger
-A INPUT -j Block
-A Block -p tcp -m tcp --tcp-flags SYN,FIN SYN,FIN -j Logger
-A Logger -j LOG --log-level 4
-A Logger -j DROP

-A INPUT -i lo -j ACCEPT
-A OUTPUT -o lo -j ACCEPT

There will be more rules in Block, but I just want to understand the logic.

1.) How is -A INPUT -j Block possible before there are any rules appended to Block, does that mean iptables first searches and assembles all rules that belong to custom chains regardless of order? Same for Logger.

2.)
Would this be OK to log and drop all rules in in Block?
I am worried because there are four jumps, INPUT -> Block -> Logger -> LOG -> Logger -> DROP

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Is this even POSSIBLE? linux_forum1 <linux_forum1@protonmail.com> - 2022-01-06 19:00 +0100
  Re: Is this even POSSIBLE? Dan Ritter <dsr@randomstring.org> - 2022-01-06 20:00 +0100
    Re: Is this even POSSIBLE? linux_forum1 <linux_forum1@protonmail.com> - 2022-01-06 21:20 +0100
      RE: Is this even POSSIBLE? linux_forum1 <linux_forum1@protonmail.com> - 2022-01-07 10:30 +0100

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