Fat line - Animating from tip to tail


I am trying to animate randomly created fat lines from tip to tail. Here is a my example:

Edit fiddle - JSFiddle - Code Playground (sometimes it takes an extra refresh, dont know why…)

It seems my lines render from the middle of segments instead of animating smoothly from the start to the end of the line.

Does anyone have a suggestion or a different approach? I am fairly new to ThreeJS. Thank you for your help!

I’ve had a little success by switching to a dashed line and animating the dash to grow

But now I am getting slight breaks in the line that I can’t seem to remove.