diff --git a/src/topics/thumbs.js b/src/topics/thumbs.js
index c3ddd5a0b4..ab7532dd4d 100644
--- a/src/topics/thumbs.js
+++ b/src/topics/thumbs.js
@@ -42,13 +42,13 @@ Thumbs.get = async function (tids) {
 Thumbs.associate = async function ({ id, path: relativePath, url }) {
 	// Associates a newly uploaded file as a thumb to the passed-in draft or topic
 	const isDraft = validator.isUUID(String(id));
-	const value = relativePath || url;
+	let value = relativePath || url;
 	const set = `${isDraft ? 'draft' : 'topic'}:${id}:thumbs`;
 	const numThumbs = await db.sortedSetCard(set);
 
 	// Normalize the path to allow for changes in upload_path (and so upload_url can be appended if needed)
 	if (relativePath) {
-		relativePath = relativePath.replace(nconf.get('upload_path'), '');
+		value = value.replace(nconf.get('upload_path'), '');
 	}
 
 	db.sortedSetAdd(set, numThumbs, value);
diff --git a/test/topicThumbs.js b/test/topicThumbs.js
index 550337a698..5024a96cc9 100644
--- a/test/topicThumbs.js
+++ b/test/topicThumbs.js
@@ -29,6 +29,7 @@ describe('Topic thumbs', () => {
 	let fooCSRF;
 	let fooUid;
 	const thumbPaths = [`${nconf.get('upload_path')}/files/test.png`, `${nconf.get('upload_path')}/files/test2.png`, 'https://example.org'];
+	const relativeThumbPaths = thumbPaths.map(path => path.replace(nconf.get('upload_path'), ''));
 	const uuid = utils.generateUUID();
 
 	function createFiles() {
@@ -112,7 +113,7 @@ describe('Topic thumbs', () => {
 				path: thumbPaths[0],
 			});
 
-			const exists = await db.isSortedSetMember(`topic:2:thumbs`, thumbPaths[0]);
+			const exists = await db.isSortedSetMember(`topic:2:thumbs`, relativeThumbPaths[0]);
 			assert(exists);
 		});
 
@@ -122,7 +123,7 @@ describe('Topic thumbs', () => {
 				path: thumbPaths[1],
 			});
 
-			const exists = await db.isSortedSetMember(`draft:${uuid}:thumbs`, thumbPaths[1]);
+			const exists = await db.isSortedSetMember(`draft:${uuid}:thumbs`, relativeThumbPaths[1]);
 			assert(exists);
 		});
 
@@ -132,7 +133,7 @@ describe('Topic thumbs', () => {
 				path: thumbPaths[2],
 			});
 
-			const exists = await db.isSortedSetMember(`topic:2:thumbs`, thumbPaths[2]);
+			const exists = await db.isSortedSetMember(`topic:2:thumbs`, relativeThumbPaths[2]);
 			assert(exists);
 		});
 	});
@@ -147,7 +148,7 @@ describe('Topic thumbs', () => {
 				{
 					id: 2,
 					name: 'test.png',
-					url: `${nconf.get('upload_url')}${thumbPaths[0]}`,
+					url: `${nconf.get('upload_url')}${relativeThumbPaths[0]}`,
 				},
 				{
 					id: 2,
@@ -157,7 +158,7 @@ describe('Topic thumbs', () => {
 				{
 					id: 2,
 					name: 'test2.png',
-					url: `${nconf.get('upload_url')}${thumbPaths[1]}`,
+					url: `${nconf.get('upload_url')}${relativeThumbPaths[1]}`,
 				},
 			]);
 		});
@@ -169,10 +170,10 @@ describe('Topic thumbs', () => {
 				id: 1,
 				path: thumbPaths[0],
 			});
-			await topics.thumbs.delete(1, thumbPaths[0]);
+			await topics.thumbs.delete(1, relativeThumbPaths[0]);
 
-			assert.strictEqual(await db.isSortedSetMember('topic:1:thumbs', thumbPaths[0]), false);
-			assert.strictEqual(await file.exists(`${nconf.get('upload_path')}${thumbPaths[0]}`), false);
+			assert.strictEqual(await db.isSortedSetMember('topic:1:thumbs', relativeThumbPaths[0]), false);
+			assert.strictEqual(await file.exists(thumbPaths[0]), false);
 		});
 
 		it('should also work with UUIDs', async () => {
@@ -180,10 +181,10 @@ describe('Topic thumbs', () => {
 				id: uuid,
 				path: thumbPaths[1],
 			});
-			await topics.thumbs.delete(uuid, thumbPaths[1]);
+			await topics.thumbs.delete(uuid, relativeThumbPaths[1]);
 
-			assert.strictEqual(await db.isSortedSetMember(`draft:${uuid}:thumbs`, thumbPaths[1]), false);
-			assert.strictEqual(await file.exists(`${nconf.get('upload_path')}${thumbPaths[1]}`), false);
+			assert.strictEqual(await db.isSortedSetMember(`draft:${uuid}:thumbs`, relativeThumbPaths[1]), false);
+			assert.strictEqual(await file.exists(thumbPaths[1]), false);
 		});
 
 		it('should also work with URLs', async () => {
@@ -191,15 +192,15 @@ describe('Topic thumbs', () => {
 				id: uuid,
 				path: thumbPaths[2],
 			});
-			await topics.thumbs.delete(uuid, thumbPaths[2]);
+			await topics.thumbs.delete(uuid, relativeThumbPaths[2]);
 
-			assert.strictEqual(await db.isSortedSetMember(`draft:${uuid}:thumbs`, thumbPaths[2]), false);
+			assert.strictEqual(await db.isSortedSetMember(`draft:${uuid}:thumbs`, relativeThumbPaths[2]), false);
 		});
 
 		it('should not delete the file from disk if not associated with the tid', async () => {
 			createFiles();
 			await topics.thumbs.delete(uuid, thumbPaths[0]);
-			assert.strictEqual(await file.exists(`${nconf.get('upload_path')}${thumbPaths[0]}`), true);
+			assert.strictEqual(await file.exists(thumbPaths[0]), true);
 		});
 	});