diff --git a/packages/query-devtools/src/__tests__/TanstackQueryDevtools.test.tsx b/packages/query-devtools/src/__tests__/TanstackQueryDevtools.test.tsx
index 01c8969f3a..cef4475d83 100644
--- a/packages/query-devtools/src/__tests__/TanstackQueryDevtools.test.tsx
+++ b/packages/query-devtools/src/__tests__/TanstackQueryDevtools.test.tsx
@@ -56,4 +56,61 @@ describe('TanstackQueryDevtools', () => {
       expect(() => devtools.unmount()).toThrow('Devtools is not mounted')
     })
   })
+
+  describe('setters', () => {
+    describe('before mount', () => {
+      it('should not throw when "setButtonPosition" is called', () => {
+        expect(() => devtools.setButtonPosition('top-left')).not.toThrow()
+      })
+
+      it('should not throw when "setPosition" is called', () => {
+        expect(() => devtools.setPosition('left')).not.toThrow()
+      })
+
+      it('should not throw when "setInitialIsOpen" is called', () => {
+        expect(() => devtools.setInitialIsOpen(true)).not.toThrow()
+      })
+
+      it('should not throw when "setErrorTypes" is called', () => {
+        expect(() =>
+          devtools.setErrorTypes([
+            { name: 'NetworkError', initializer: () => new Error('Network') },
+          ]),
+        ).not.toThrow()
+      })
+
+      it('should not throw when "setClient" is called', () => {
+        expect(() => devtools.setClient(new QueryClient())).not.toThrow()
+      })
+
+      it('should not throw when "setTheme" is called', () => {
+        expect(() => devtools.setTheme('dark')).not.toThrow()
+        expect(() => devtools.setTheme('light')).not.toThrow()
+        expect(() => devtools.setTheme('system')).not.toThrow()
+        expect(() => devtools.setTheme(undefined)).not.toThrow()
+      })
+    })
+
+    describe('after mount', () => {
+      it('should not throw when setters are called on a mounted instance', () => {
+        const el = document.createElement('div')
+        devtools.mount(el)
+
+        try {
+          expect(() => devtools.setButtonPosition('top-left')).not.toThrow()
+          expect(() => devtools.setPosition('left')).not.toThrow()
+          expect(() => devtools.setInitialIsOpen(true)).not.toThrow()
+          expect(() =>
+            devtools.setErrorTypes([
+              { name: 'NetworkError', initializer: () => new Error('Network') },
+            ]),
+          ).not.toThrow()
+          expect(() => devtools.setClient(new QueryClient())).not.toThrow()
+          expect(() => devtools.setTheme('dark')).not.toThrow()
+        } finally {
+          devtools.unmount()
+        }
+      })
+    })
+  })
 })
diff --git a/packages/query-devtools/src/__tests__/TanstackQueryDevtoolsPanel.test.tsx b/packages/query-devtools/src/__tests__/TanstackQueryDevtoolsPanel.test.tsx
index 1993ef6779..f7407ad5ff 100644
--- a/packages/query-devtools/src/__tests__/TanstackQueryDevtoolsPanel.test.tsx
+++ b/packages/query-devtools/src/__tests__/TanstackQueryDevtoolsPanel.test.tsx
@@ -56,4 +56,66 @@ describe('TanstackQueryDevtoolsPanel', () => {
       expect(() => devtools.unmount()).toThrow('Devtools is not mounted')
     })
   })
+
+  describe('setters', () => {
+    describe('before mount', () => {
+      it('should not throw when "setButtonPosition" is called', () => {
+        expect(() => devtools.setButtonPosition('top-left')).not.toThrow()
+      })
+
+      it('should not throw when "setPosition" is called', () => {
+        expect(() => devtools.setPosition('left')).not.toThrow()
+      })
+
+      it('should not throw when "setInitialIsOpen" is called', () => {
+        expect(() => devtools.setInitialIsOpen(true)).not.toThrow()
+      })
+
+      it('should not throw when "setErrorTypes" is called', () => {
+        expect(() =>
+          devtools.setErrorTypes([
+            { name: 'NetworkError', initializer: () => new Error('Network') },
+          ]),
+        ).not.toThrow()
+      })
+
+      it('should not throw when "setClient" is called', () => {
+        expect(() => devtools.setClient(new QueryClient())).not.toThrow()
+      })
+
+      it('should not throw when "setOnClose" is called', () => {
+        expect(() => devtools.setOnClose(() => {})).not.toThrow()
+      })
+
+      it('should not throw when "setTheme" is called', () => {
+        expect(() => devtools.setTheme('dark')).not.toThrow()
+        expect(() => devtools.setTheme('light')).not.toThrow()
+        expect(() => devtools.setTheme('system')).not.toThrow()
+        expect(() => devtools.setTheme(undefined)).not.toThrow()
+      })
+    })
+
+    describe('after mount', () => {
+      it('should not throw when setters are called on a mounted instance', () => {
+        const el = document.createElement('div')
+        devtools.mount(el)
+
+        try {
+          expect(() => devtools.setButtonPosition('top-left')).not.toThrow()
+          expect(() => devtools.setPosition('left')).not.toThrow()
+          expect(() => devtools.setInitialIsOpen(true)).not.toThrow()
+          expect(() =>
+            devtools.setErrorTypes([
+              { name: 'NetworkError', initializer: () => new Error('Network') },
+            ]),
+          ).not.toThrow()
+          expect(() => devtools.setClient(new QueryClient())).not.toThrow()
+          expect(() => devtools.setOnClose(() => {})).not.toThrow()
+          expect(() => devtools.setTheme('dark')).not.toThrow()
+        } finally {
+          devtools.unmount()
+        }
+      })
+    })
+  })
 })
diff --git a/packages/query-devtools/src/__tests__/utils.test.ts b/packages/query-devtools/src/__tests__/utils.test.ts
index 0c1fb6ec50..07dff9ece4 100644
--- a/packages/query-devtools/src/__tests__/utils.test.ts
+++ b/packages/query-devtools/src/__tests__/utils.test.ts
@@ -539,6 +539,38 @@ describe('Utils tests', () => {
     `)
     })
 
+    describe('array nested path', () => {
+      it('should delete nested data inside an array correctly', () => {
+        const oldData = [
+          { id: 1, title: 'first' },
+          { id: 2, title: 'second' },
+        ]
+
+        const newData = deleteNestedDataByPath(oldData, ['1', 'title'])
+
+        expect(newData).not.toBe(oldData)
+        expect(newData).toMatchInlineSnapshot(`
+          [
+            {
+              "id": 1,
+              "title": "first",
+            },
+            {
+              "id": 2,
+            },
+          ]
+        `)
+      })
+    })
+
+    describe('primitive', () => {
+      it('should return primitive data as-is when it is not an Object/Array/Map/Set', () => {
+        expect(deleteNestedDataByPath(42, ['x'])).toBe(42)
+        expect(deleteNestedDataByPath('hello', ['x'])).toBe('hello')
+        expect(deleteNestedDataByPath(null, ['x'])).toBe(null)
+      })
+    })
+
     describe('nested data', () => {
       it('should delete nested items correctly', () => {
         /* eslint-disable cspell/spellchecker */
@@ -1114,6 +1146,37 @@ describe('Utils tests', () => {
         }
       })
 
+      it('should place a stale query after a fresh one when both are idle and have observers', () => {
+        const staleObserver = new QueryObserver(queryClient, {
+          queryKey: ['stale'],
+          staleTime: 0,
+        })
+        const staleUnsubscribe = staleObserver.subscribe(() => {})
+        const stale = queryClient.getQueryCache().find({ queryKey: ['stale'] })!
+        stale.setState({
+          ...stale.state,
+          fetchStatus: 'idle',
+          data: 'data',
+          dataUpdatedAt: 200,
+        })
+
+        const fresh = buildQuery(['fresh'], {
+          fetchStatus: 'idle',
+          data: 'fresh-data',
+          dataUpdatedAt: 100,
+        })
+        const freshUnsubscribe = addObserver(fresh)
+
+        try {
+          expect(stale.isStale()).toBe(true)
+          expect(statusSort(fresh, stale)).toBe(-1)
+          expect(statusSort(stale, fresh)).toBe(1)
+        } finally {
+          staleUnsubscribe()
+          freshUnsubscribe()
+        }
+      })
+
       it('should fall back to "last updated" sort within the same status rank', () => {
         const older = buildQuery(['older'], { dataUpdatedAt: 100 })
         const newer = buildQuery(['newer'], { dataUpdatedAt: 200 })