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Note that when you apply replace or remove patches, make sure you match your file structure and file location with the target XML you wish to replace or remove, or else funny things might occur.
For your interest, starting from v4.0 RC3, you can add silent="true" attribute to any add, replace or remove node to suppress errors when any is produced during loading. This can be useful to create overrides to other mods as 'optional' content and not show up as errors when the other mods are not present.
Add Patch
This patch method adds new content into the vanilla XML when the game processes the mods.
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