Thanks, that helped. There were quite some files in there. First removed those with a number at the end. That didn't help. Removing all did. I'm testing on an additional PC, and this solved it. Before I do so on my FG machine, what am I losing?
I can reproduce now. If I copy the files below to a test campaign, the entries get doubled. I uploaded one of them for reproduction, should you be interested. Just drop it in your ModuleDB folder. It will duplicate you PHB only.
Code:5E Background Proficiencies, Languages, and Features.xml
5E Background Proficiencies, Languages, and Features_1605264632.xml
5E Class List Quick Start.xml
5E Conditions & Effects.xml
5E Conditions & Effects_1602258644.xml
5E Conditions & Effects_1609404585.xml
5E Conditions & Effects_1613326669.xml
5E Effects Coding - Class Features_1593164493.xml
5E Effects Coding - Class Features_1602258643.xml
5E Effects Coding - Class Features_1605814938.xml
5E Effects Coding - Class Features_1606164267.xml
5E Effects Coding - Class Features_1606735118.xml
5E Effects Coding - Class Features_1607077646.xml
5E Effects Coding - Class Features_1608975246.xml
5E Effects Coding - Class Features_1609404584.xml
5E Effects Coding - Class Features_1610715656.xml
5E Effects Coding - Class Features_1612556140.xml
5E Effects Coding - Feats_1605814939.xml
5E Effects Coding - Feats_1608975247.xml
5E Effects Coding - Spells_1593164494.xml
5E Effects Coding - Spells_1602258645.xml
5E Effects Coding - Spells_1602937519.xml
5E Effects Coding - Spells_1605814940.xml
5E Effects Coding - Spells_1606735119.xml
5E Effects Coding - Spells_1608975249.xml
5E Feat List with Benefits.xml
5E Feat List with Benefits_1606735120.xml
5E Items Effects Coding - Adventuring Gear.xml
5E Items Effects Coding - Armor.xml
5E Items Effects Coding - Potions.xml
5E Items Effects Coding - Rings.xml
5E Items Effects Coding - Rods.xml
5E Items Effects Coding - Rods_1602941217.xml
5E Items Effects Coding - Rods_1602942257.xml
5E Items Effects Coding - Staffs.xml
5E Items Effects Coding - Wands.xml
5E Items Effects Coding - Weapons.xml
5E Items Effects Coding - Wondrous Items.xml
5E Items Effects Coding - Wondrous Items_1608975248.xml
5E Race Ability Modifiers & Key Class Stats.xml
5E Spells (and Cantrips) Known, Prepared, Recovery per Class.xml
Content Generator 2020 5e.xml
Critically Awesome Essentials Module - 5e DM Tools.xml
Critically Awesome Essentials Module - 5e Player Tools.xml
Crypt of the Sun Lord.xml
D&D Sword Coast Adventurer's Guide - Campaign Guide.xml
D&D Sword Coast Adventurer's Guide - Campaign Guide_1607005967.xml
D&D Sword Coast Adventurer's Guide - Player's Guide.xml
D&D Sword Coast Adventurer's Guide - Player's Guide_1607005968.xml
D&D Sword Coast Adventurer's Guide - Player's Guide_1607029443.xml
D&D Sword Coast Adventurer's Guide - Player's Guide_1610038771.xml
DD Dungeon Masters Guide - Maps.xml
DD Dungeon Masters Guide - Maps_1582963670.xml
DD Dungeon Masters Guide - Maps_1591729988.xml
DD Dungeon Masters Guide - Maps_1602691813.xml
DD Dungeon Masters Guide - Players.xml
DD Dungeon Masters Guide_1582963665.xml
DD Dungeon Masters Guide_1588235493.xml
DD Dungeon Masters Guide_1591729987.xml
DD Dungeon Masters Guide_1594149515.xml
DD Dungeon Masters Guide_1598299005.xml
DD Dungeon Masters Guide_1598383229.xml
DD MM Monster Manual_1591729989.xml
DD MM Monster Manual_1595437753.xml
DD MM Monster Manual_1611393953.xml
DD MM Monster Manual_1611394855.xml
DD PHB Deluxe.xml
DD PHB Deluxe_1591729991.xml
DD PHB Deluxe_1602258650.xml
DD PHB Deluxe_1606410184.xml
DD PHB Deluxe_1610038779.xml
DD Xanathar's Guide to Everything Players.xml
DD Xanathar's Guide to Everything Players_1610038782.xml
DD Xanathar's Guide to Everything.xml
DD Xanathar's Guide to Everything_1598299011.xml
DD5E SRD Bestiary.xml
DD5E SRD Bestiary_1561733500.xml
DD5E SRD Bestiary_1582963681.xml
removed.txt
Shops Examples 5E.xml
Token Share Module.xml
Tool Proficiencies as Skills.xml
UM Gemstones with Tables.xml
UM Gemstones.xml
Zinderende Zomer Zessies.xml