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Mass Electrification

Allows you to electrify all rails in one go. Press Control while using the electrification tool on a non-electrified piece of rail, to extend the selection to all connected non-electrified track.
It seems like the game doesn't like electrifying that much track at once, so it won't show the power lines immediately. Save and reload your game, then the new lines will be rendered correctly.

Source: https://github.com/jorn86/VoxelTycoonMods
Changelog: https://github.com/jorn86/VoxelTycoonMods/blob/master/MassElectrification/changelog.md

Version 0.1.1