Not sure how long we'll still have access to the "Align Euler to Vector", but I saw on the 4.2 New features YT video that it has been replaced for "Align Rotation to Vector". It now shows a little warning sign "Deprecated".
Not sure if it changed anything other than the name, but the settings are exactly the same and it worked without any issues on the new version of Blender. So easy peezy!
Most of the change is under the hood so to speak. From my understanding it follows closer to how Blender works. I also read that it is to make Blender more compatible with studio pipelines but I'm taking that with a grain of salt since I haven't seen anything from a trusted source.