Chaining pipe objects; sometimes allowed, sometimes not

I've found that sometimes I've managed to chain liquid bridges etc. but most of the time I can't (I'm not sure how I did). I'm not sure which one is the bug but I'm in favour of allowing chaining for greater flexibility. But a problem presents when you chain in series, I've put an example of that below with a primitive mock up of a potential solution. It was a white input symbol before I editted the screenshot.