So I am gonna build a bashrc from scratch again.

There is just one thing messes me right now:
I don't know how to avoid the bug(?) described at the bottom.

Last time when I made one, used a line break, but whenever I went back in the command history and there is a long command (chain) it just messes up whole PS1 by getting inside, pressing backspace furiously to get the start of the command (mostly eating half of the PS1) and an up and a down to get back to command and see it properly.

Any good ideas to destroy that bug while it isn't born yet?