# In UE 5.8 File diffs for InputMappingContext and InputAction no longer use the Details/Property diff window and open a text diff instead 

**URL:** <https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845>\
**Category:** Programming & Scripting\
**Tags:** unreal-engine, Epic-Pro-Support, question\
**Created:** [September 30, 2026, 10:27am UTC](https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845 "2026-09-30T10:27:07Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![anonymous-edc](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous-edc](https://forums.unrealengine.com/u/anonymous-edc)\
**Post date:** [September 30, 2026, 10:27am UTC](https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845/1 "2026-09-30T10:27:07Z")

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As described - the diff tool for InputAction and InputMappingContext assets uses a text diff in 5.8, whereas in 5.7 it used to use a more user-friendly GUI.

This seems to be because UAssetDefinition\_InputAction and UAssetDefinition\_InputMappingContext were added at some point.

We are using 5.8.3 specifically, which is the first update we’ve done from 5.7.\* -\> 5.8.

Our local fix is to change the newly added AssetDefinitions to derive from UAssetDefinition\_ **DataAsset** instead of UAssetDefinition **Default**.

Thanks,

Dave

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**Author:** ![anonymous-edc](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous-edc](https://forums.unrealengine.com/u/anonymous-edc)\
**Post date:** [September 30, 2026, 10:27am UTC](https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845/2 "2026-09-30T10:27:09Z")

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**Steps to Reproduce**

- In editor (with a source controlled environment), create or make a change to an InputAction and an InputContextMapping asset.
- Right click the asset in the content browser and choose ‘Revision Control’ -\> ‘Diff Against Depot’

By default in UE 5.8 a text diff will open which is much more difficult to read.

In 5.7 a details/property diff would open (using the editor GUI) which was much easier to read.

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**Author:** ![Cody.Albert](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/cody.albert/32/1088813_2.png) [@Cody.Albert](https://forums.unrealengine.com/u/Cody.Albert)\
**Post date:** [October 3, 2026, 1:03am UTC](https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845/3 "2026-10-03T01:03:29Z")

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Hi,

Good catch, I’ll see about getting that fixed for the next release. Thanks!

Best,

Cody

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<div class="post-metadata">

**Author:** ![Cody.Albert](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/cody.albert/32/1088813_2.png) [@Cody.Albert](https://forums.unrealengine.com/u/Cody.Albert)\
**Post date:** [October 12, 2026, 7:01pm UTC](https://forums.unrealengine.com/t/in-ue-5-8-file-diffs-for-inputmappingcontext-and-inputaction-no-longer-use-the-details-property-diff-window-and-open-a-text-diff-instead/2853845/4 "2026-10-12T19:01:12Z")

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Hi,

This has been checked in at CL# 59188850. Thanks again!