Modifying equipped flasks does not show negative stat differences

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• I'm running the latest version of Path of Building and I've verified this by checking the changelog

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• I've checked for duplicate open and closed issues by using the search function of the issue tracker

What platform are you running Path of Building on?

Windows

How is Path of Building expected to behave?

If I modify an equipped flask by lowering the values of some mods, I'd expect the stat differences to show the results.

How does Path of Building behave?

If I modify an equipped flask by lowering the values of some mods, the resulting negative stat differences aren't shown, only the positive ones.

How to reproduce the issue

1. Craft a Granite Flask with the mod ˙50% increased Armour during Effect
2. Save it
3. Modify the flask by increasing the armour value - you should see Activating this flask will give you and some positive armour increase
4. Modify the flask by decreasing the armour value - the stat differences aren't displayed

PoB for PoE1 build code

Screenshots

Starting from 50% increased Armour:

Start by reproducing the issue in Path of Building with an equipped Granite Flask, first increasing and then decreasing its armour modifier. Trace the code responsible for displaying flask stat differences; done means negative differences are displayed as well as positive ones.