I have finally decided to do what I've been thinking about doing for some time: resurrecting pgAdmin3 and fixing it so it supports PostgreSQL versions from 10 onwards. For v10 pgAdmin3 basically works, there are some complaints but it allows basic operation. For 11 there are a lot more error messages and issues.
Why do this? pgAdmin4 is not a tool for me. There is a lot of development happening around it but it is definitely not something I want to use. It's clunky, it's missing basic functionality, editing things is cumbersome etc. I haven't checked the latest and greatest, but I did check it a month or two ago and it wasn't much better. I need a simple tool to handle databases, run queries, edit data etc and pgAdmin3 does it all for me. So why not maintain it and fix the parts that have broken in newer PostgreSQL versions?
I have already created a repository on GitHub and changed the parts of pgAdmin3 that immediately throw errors on connecting, editing data in tables etc with 10 and 11. It is in no way a complete version and at the moment there are no binaries available. Work will continue when I have time and find things to fix. I'm not a super user with pgAdmin3 in any shape or form so I can't easily determine everything that's broken. But things will hopefully go forward.
In the future binaries will be available for 64bit Windows versions. This due to PostgreSQL 11 by default not providing binaries for 32bit Windows. So I will only compile it for that. If someone really needs 32bit version and can provide a compiled version it can probably be added.
I will also compile the binary with Windows 10 SDK which will probably exclude Windows XP from supported systems, but shouldn't exclude other common versions. If it does I will have to add compiler tools for Windows 7 and handle things with that. Testing is needed and I don't currently have Windows 7 at hand to test it.
I have contacted the pgAdmin development team and asked for advise in this matter. As far as I understand this is all fine and legal, but I want to know if they want me to somehow mention in the application that it is an unofficial port or something else. I want to do this by the book so that it will not cause problems to anyone and we can have our beloved pgAdmin3 back in a useful state.
From comments I heard that BigSQL has already made a version for PostgreSQL 10 but they don't seem to provide source code for it so I can't see what they fixed. Will have to see if it's possible to get their patches and go from there, or do I have to do it all over again myself.