Pipe Connector not reverted

Delete the coal maker.
Expected: pipe connector reverts into a 90° pipe.
Observed: Connector stays a connector.
To turn it into a pipe again, only way I found is to delete the connector and build a new pipe.

It's by design, connector won't turn into a pipe unless there is pipe on at least one side. (If it did, it would make it easier to exploit for free construction parts.)

You can place connector for free. Demolish pipe gives you parts back.

Maybe connectors should not be for free. Unfortunately, as one size fits all, having different prices for different possible thruputs needs some thought:

• Connectors on ghost pipes cost like the highest pipe connected to.
• Connectors on existing pipes are already paid for.
• Standalone connectors do not get build without being attached to something. So, they could cost just 1 CP1, no matter their actual size.
• If someone later adds a higher pipe, the "upgrade" of the connector can be paid with the new pipe.

Yeah, it's quite a hard problem to solve

Maybe they can just cost one rubber or something?

Whatever price the matching transport does cost (I only thought of pipes, you are right, belts need rubber, too). It's just a bit complex and thus error prone.
Otoh, it eliminates the exploit, so there is a certain gain.
Is that exploit an issue, with all those mods out there? I mean does it distort the game of someone who does not want to exploit it, but just randomly, occasionally runs into it? I feel this exploitability is a non issue, i.e. the connector could just become a pipe.

Anyways, I thought that behavior was normal?

Sometimes the connector changes when I dont want it to change.

I don't really think making the connectors cost something makes the game better IMO, nor does having multiple costs. It just makes things more complicated for no real reason.

Unfortunately, it's quite exploitable

Not by random chance, though. It has to be done conciously to have an impact