diff --git a/chrome/content/zotero/xpcom/data/items.js b/chrome/content/zotero/xpcom/data/items.js
index 4ae77f46b0..2f783f29c4 100644
--- a/chrome/content/zotero/xpcom/data/items.js
+++ b/chrome/content/zotero/xpcom/data/items.js
@@ -820,7 +820,21 @@ Zotero.Items = function() {
 				// Add tags to master
 				var tags = otherItem.getTags();
 				for (let j = 0; j < tags.length; j++) {
-					item.addTag(tags[j].tag);
+					let tagName = tags[j].tag;
+					if (item.hasTag(tagName)) {
+						let type = item.getTagType(tagName);
+						// If existing manual tag, leave that
+						if (type == 0) {
+							continue;
+						}
+						// Otherwise, add the non-master item's tag, which may be manual, in which
+						// case it will remain at the end
+						item.addTag(tagName, tags[j].type);
+					}
+					// If no existing tag, add with the type from the non-master item
+					else {
+						item.addTag(tagName, tags[j].type);
+					}
 				}
 				
 				// Add relation to track merge
diff --git a/test/tests/itemsTest.js b/test/tests/itemsTest.js
index eedf08d89d..ec16ea440c 100644
--- a/test/tests/itemsTest.js
+++ b/test/tests/itemsTest.js
@@ -200,6 +200,32 @@ describe("Zotero.Items", function () {
 			assert.equal(item1.dateAdded, '2019-01-01 00:00:00');
 		});
 		
+		it("should keep automatic tag on non-master item as automatic", async function () {
+			var item1 = await createDataObject('item', { tags: [{ tag: 'A' }] });
+			var item2 = await createDataObject('item', { tags: [{ tag: 'B', type: 1 }] });
+			await Zotero.Items.merge(item1, [item2]);
+			var tags = item1.getTags();
+			var tag = tags.find(x => x.tag == 'B');
+			assert.propertyVal(tag, 'type', 1);
+		});
+		
+		it("should skip automatic tag on non-master item that exists as manual tag on master", async function () {
+			var item1 = await createDataObject('item', { tags: [{ tag: 'A' }, { tag: 'B' }] });
+			var item2 = await createDataObject('item', { tags: [{ tag: 'B', type: 1 }] });
+			await Zotero.Items.merge(item1, [item2]);
+			var tags = item1.getTags();
+			var tag = tags.find(x => x.tag == 'B');
+			assert.notProperty(tag, 'type');
+		});
+		
+		it("should keep automatic tag on master if it also exists on non-master item", async function () {
+			var item1 = await createDataObject('item', { tags: [{ tag: 'B', type: 1 }] });
+			var item2 = await createDataObject('item', { tags: [{ tag: 'B', type: 1 }] });
+			await Zotero.Items.merge(item1, [item2]);
+			var tags = item1.getTags();
+			assert.propertyVal(tags[0], 'type', 1);
+		});
+		
 		it("should merge two items when servant is linked to an item absent from cache", function* () {
 			// two group libraries
 			var groupOneInfo = yield createGroup({