perf: Limit Chapter Neighbor Queries To One Row

* feat: volume navigation and disable animation settings for paged reading

* fix: transition style removal

* fix: pageReader incorrect initialization

* fix: remove unneeded check

* chore: update Vietnamese translations for paged reading settings

assets/reader/css/pageReader.css

@@ -15,6 +15,12 @@ body.page-reader > #LNReader-chapter {
   column-fill: auto;
   transition: transform 200ms;
 }
+body.page-reader.no-animation > #LNReader-chapter {
+  transition: none !important;
+}
+body.page-reader.no-animation .transition-chapter {
+  transition: none !important;
+}
 .transition-chapter {
   height: 100vh;
   width: 100vw;

assets/reader/js/core.js

@@ -524,7 +524,8 @@ van.derive(() => {
   }
 });
 
-window.pageReader = new (function () {
+var pageReader;
+window.pageReader = pageReader = new (function () {
   const config =
     typeof initialPageReaderConfig === 'undefined'
       ? {}
@@ -544,18 +545,21 @@ window.pageReader = new (function () {
         document.getElementsByClassName('transition-chapter')[0];
       if (!this.chapterEnding) return;
     }
+    const noAnim = Boolean(
+      reader.generalSettings?.val?.pageReaderDisableAnimation,
+    );
     this.chapterEnding.style.transition = 'unset';
     if (bool) {
       this.chapterEnding.style.transform = `translateX(${left ? -200 : 0}vw)`;
       requestAnimationFrame(() => {
-        if (!instant) {
+        if (!instant && !noAnim) {
           this.chapterEnding.style.transition = 'transform 200ms';
         }
         this.chapterEnding.style.transform = 'translateX(-100vw)';
       });
       this.chapterEndingVisible.val = true;
     } else {
-      if (!instant) {
+      if (!instant && !noAnim) {
         this.chapterEnding.style.transition = 'transform 200ms';
       }
       this.chapterEnding.style.transform = `translateX(${left ? -200 : 0}vw)`;
@@ -579,26 +583,35 @@ window.pageReader = new (function () {
       return;
     }
     destPage = parseInt(destPage, 10);
+    const noAnim = Boolean(
+      reader.generalSettings?.val?.pageReaderDisableAnimation,
+    );
     if (destPage < 0) {
       if (!reader.prevChapter) return;
       document.getElementsByClassName('transition-chapter')[0].innerText =
         reader.prevChapter.name;
-      this.showChapterEnding(true, false, true);
+      this.showChapterEnding(true, noAnim, true);
       this.chapterNavigationPending = true;
-      setTimeout(() => {
-        reader.post({ type: 'prev' });
-      }, 200);
+      setTimeout(
+        () => {
+          reader.post({ type: 'prev' });
+        },
+        noAnim ? 0 : 200,
+      );
       return;
     }
     if (destPage >= this.totalPages.val) {
       if (!reader.nextChapter) return;
       document.getElementsByClassName('transition-chapter')[0].innerText =
         reader.nextChapter.name;
-      this.showChapterEnding(true);
+      this.showChapterEnding(true, noAnim);
       this.chapterNavigationPending = true;
-      setTimeout(() => {
-        reader.post({ type: 'next' });
-      }, 200);
+      setTimeout(
+        () => {
+          reader.post({ type: 'next' });
+        },
+        noAnim ? 0 : 200,
+      );
       return;
     }
     this.page.val = destPage;
@@ -606,7 +619,7 @@ window.pageReader = new (function () {
       'translateX(-' + destPage * 100 + '%)';
 
     const newProgress = parseInt(
-      ((pageReader.page.val + 1) / pageReader.totalPages.val) * 100,
+      ((this.page.val + 1) / this.totalPages.val) * 100,
       10,
     );
 
@@ -687,6 +700,18 @@ window.pageReader = new (function () {
       });
     }
   });
+
+  van.derive(() => {
+    document.body.classList.toggle(
+      'no-animation',
+      Boolean(reader.generalSettings.val.pageReaderDisableAnimation),
+    );
+    reader.chapterElement?.style.removeProperty('transition');
+    const chapterEnding =
+      this.chapterEnding ||
+      document.getElementsByClassName('transition-chapter')[0];
+    chapterEnding?.style.removeProperty('transition');
+  });
 })();
 
 document.addEventListener('DOMContentLoaded', () => {
@@ -905,7 +930,11 @@ window.addEventListener('load', () => {
       if (Math.abs(diffX) > 8 || Math.abs(diffY) > 8) {
         pageReader.ignoreClickUntil = Date.now() + 400;
       }
-      reader.chapterElement.style.transition = 'transform 200ms';
+      reader.chapterElement.style.transition = reader.generalSettings.val
+        .pageReaderDisableAnimation
+        ? 'none'
+        : 'transform 200ms';
+      reader.chapterElement.style.removeProperty('transition');
       const diffXPercentage = diffX / reader.layoutWidth;
       if (diffXPercentage < -0.3) {
         pageReader.movePage(pageReader.page.val + 1);

src/database/queries/ChapterQueries.ts

@@ -785,7 +785,9 @@ export const getPrevChapter = async (
     .orderBy(
       desc(castInt(chapterSchema.page)),
       desc(castInt(chapterSchema.position)),
+      desc(chapterSchema.id),
     )
+    .limit(1)
     .get();
 };
 
@@ -814,7 +816,9 @@ export const getNextChapter = async (
     .orderBy(
       asc(castInt(chapterSchema.page)),
       asc(castInt(chapterSchema.position)),
+      asc(chapterSchema.id),
     )
+    .limit(1)
     .get();
 };
 

src/database/queries/__tests__/ChapterQueries.test.ts

@@ -1008,6 +1008,114 @@ describe('ChapterQueries', () => {
     });
   });
 
+  describe('chapter neighbors', () => {
+    it('limits rows transferred by both neighbor lookups to one', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      for (let position = 0; position < 5; position++) {
+        await insertTestChapter(testDb, novelId, { position });
+      }
+      const client = testDb.sqlite as typeof testDb.sqlite & {
+        executeRawAsync: typeof testDb.sqlite.executeRaw;
+      };
+      const executeRaw = jest.spyOn(client, 'executeRawAsync');
+      try {
+        expect((await getNextChapter(novelId, 0, '1'))?.position).toBe(1);
+        expect((await getPrevChapter(novelId, 4, '1'))?.position).toBe(3);
+        expect(executeRaw).toHaveBeenCalledTimes(2);
+        for (const call of executeRaw.mock.calls) {
+          expect(call[0]).toMatch(/limit \?/i);
+          expect(call[1]?.at(-1)).toBe(1);
+        }
+        for (const result of executeRaw.mock.results) {
+          expect(await result.value).toHaveLength(1);
+        }
+      } finally {
+        executeRaw.mockRestore();
+      }
+    });
+
+    it('returns no neighbor before the first or after the last chapter', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      await insertTestChapter(testDb, novelId, { page: '1', position: 0 });
+      await insertTestChapter(testDb, novelId, { page: '2', position: 1 });
+
+      expect(await getPrevChapter(novelId, 0, '1')).toBeUndefined();
+      expect(await getNextChapter(novelId, 1, '2')).toBeUndefined();
+    });
+
+    it('breaks duplicate position ties by id in the navigation direction', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      const firstId = await insertTestChapter(testDb, novelId, { position: 1 });
+      const secondId = await insertTestChapter(testDb, novelId, {
+        position: 1,
+      });
+
+      expect((await getNextChapter(novelId, 0, '1'))?.id).toBe(firstId);
+      expect((await getPrevChapter(novelId, 2, '1'))?.id).toBe(secondId);
+      expect(await getNextChapter(novelId, 1, '1')).toBeUndefined();
+      expect(await getPrevChapter(novelId, 1, '1')).toBeUndefined();
+    });
+
+    it('preserves numeric-looking page comparisons and integer page ordering', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      const page1 = await insertTestChapter(testDb, novelId, { page: '1' });
+      const page02 = await insertTestChapter(testDb, novelId, { page: '02' });
+      const page2 = await insertTestChapter(testDb, novelId, { page: '2' });
+      const page10 = await insertTestChapter(testDb, novelId, { page: '10' });
+
+      // The cast parameter gives comparisons numeric affinity: '02' and '2'
+      // compare equally, and page 10 sorts after page 2.
+      expect((await getPrevChapter(novelId, 0, '2'))?.id).toBe(page1);
+      expect((await getPrevChapter(novelId, 0, '10'))?.id).toBe(page2);
+      expect((await getNextChapter(novelId, 0, '02'))?.id).toBe(page10);
+      expect((await getPrevChapter(novelId, 0, '02'))?.id).toBe(page1);
+      expect((await getNextChapter(novelId, 0, '1'))?.id).toBe(page02);
+    });
+
+    it('preserves integer-cast behavior for source-defined page labels', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      await insertTestChapter(testDb, novelId, {
+        page: 'Volume A',
+        position: 2,
+      });
+      const chapterId = await insertTestChapter(testDb, novelId, {
+        page: 'Volume B',
+        position: 0,
+      });
+
+      // Labels cast to zero, so existing eligibility treats both as later
+      // pages and sorting resolves their equal page casts by position.
+      expect(await getPrevChapter(novelId, 1, 'Volume A')).toBeUndefined();
+      expect((await getNextChapter(novelId, 1, 'Volume A'))?.id).toBe(
+        chapterId,
+      );
+    });
+
+    it('skips excluded chapters at the previous page boundary', async () => {
+      const testDb = getTestDb();
+      const novelId = await insertTestNovel(testDb);
+      const chapterId = await insertTestChapter(testDb, novelId, {
+        page: '1',
+        position: 0,
+        scanlator: null,
+      });
+      await insertTestChapter(testDb, novelId, {
+        page: '1',
+        position: 1,
+        scanlator: 'Excluded',
+      });
+
+      expect((await getPrevChapter(novelId, 0, '2', ['Excluded']))?.id).toBe(
+        chapterId,
+      );
+    });
+  });
+
   describe('getPrevChapter', () => {
     it('should return previous chapter in same page', async () => {
       const testDb = getTestDb();

src/hooks/persisted/__mocks__/useSettings.ts

@@ -66,6 +66,8 @@ export const initialChapterGeneralSettings = {
   bionicReading: false,
   tapToScroll: false,
   TTSEnable: true,
+  pageReaderInvertVolumeButtons: false,
+  pageReaderDisableAnimation: false,
 };
 
 export const initialChapterReaderSettings = {

src/hooks/persisted/useSettings.ts

@@ -194,6 +194,8 @@ export interface ChapterGeneralSettings {
   bionicReading: boolean;
   tapToScroll: boolean;
   TTSEnable: boolean;
+  pageReaderInvertVolumeButtons: boolean;
+  pageReaderDisableAnimation: boolean;
 }
 
 export interface ReaderTheme {
@@ -319,6 +321,8 @@ export const initialChapterGeneralSettings: ChapterGeneralSettings = {
   bionicReading: false,
   tapToScroll: false,
   TTSEnable: true,
+  pageReaderInvertVolumeButtons: false,
+  pageReaderDisableAnimation: false,
 };
 
 export const initialChapterReaderSettings: ChapterReaderSettings = {

src/i18n/languages/en/strings.json

@@ -668,6 +668,10 @@
       "padding": "Padding",
       "pageReader": "Paged reading (Experimental)",
       "pageReaderDescription": "Split the chapter into pages instead of scrolling. Experimental — may break formatting in some novels",
+      "invertVolumeButtons": "Invert volume buttons",
+      "invertVolumeButtonsDescription": "Swap volume up and down buttons for previous and next page",
+      "disablePageTransitions": "Disable page transition animation",
+      "disablePageTransitionsDescription": "Turn pages instantly without slide animation",
       "removeExtraSpacing": "Remove extra spacing",
       "removeExtraSpacingDescription": "Collapse extra blank lines between paragraphs",
       "scrollAmount": "Scroll amount (screen height by default)",

src/i18n/languages/vi_VN/strings.json

@@ -662,8 +662,12 @@
       "lineHeight": "Line height",
       "navigation": "Navigation",
       "padding": "Khoảng đệm",
-      "pageReader": "Paged reading (Experimental)",
-      "pageReaderDescription": "Split the chapter into pages instead of scrolling. Experimental — may break formatting in some novels",
+      "pageReader": "Đọc phân trang (Thử nghiệm)",
+      "pageReaderDescription": "Phân chương ra thành trang thay vì scroll. Thử nghiệm - có thể làm hỏng format một số tiểu thuyết",
+      "invertVolumeButtons": "Đảo nút âm lượng",
+      "invertVolumeButtonsDescription": "Đảo nút tăng và giảm âm lượng cho trang trước và sau",
+      "disablePageTransitions": "Tắt hoạt hình chuyển trạng thái trang",
+      "disablePageTransitionsDescription": "Chuyển trang ngay lập tức mà không dùng hoạt hình trượt",
       "removeExtraSpacing": "Remove extra spacing",
       "removeExtraSpacingDescription": "Collapse extra blank lines between paragraphs",
       "scrollAmount": "Scroll amount (screen height by default)",

src/i18n/types/index.ts

@@ -566,6 +566,10 @@ export interface StringMap {
   'readerScreen.bottomSheet.padding': 'string';
   'readerScreen.bottomSheet.pageReader': 'string';
   'readerScreen.bottomSheet.pageReaderDescription': 'string';
+  'readerScreen.bottomSheet.invertVolumeButtons': 'string';
+  'readerScreen.bottomSheet.invertVolumeButtonsDescription': 'string';
+  'readerScreen.bottomSheet.disablePageTransitions': 'string';
+  'readerScreen.bottomSheet.disablePageTransitionsDescription': 'string';
   'readerScreen.bottomSheet.removeExtraSpacing': 'string';
   'readerScreen.bottomSheet.removeExtraSpacingDescription': 'string';
   'readerScreen.bottomSheet.scrollAmount': 'string';

src/screens/reader/components/ReaderBottomSheet/ReaderBottomSheet.tsx

@@ -138,6 +138,19 @@ const navigationPreferences: GeneralPreference[] = [
   },
 ];
 
+const pagedModePreferences: GeneralPreference[] = [
+  {
+    key: 'pageReaderInvertVolumeButtons',
+    label: 'invertVolumeButtons',
+    description: 'invertVolumeButtonsDescription',
+  },
+  {
+    key: 'pageReaderDisableAnimation',
+    label: 'disablePageTransitions',
+    description: 'disablePageTransitionsDescription',
+  },
+];
+
 const GeneralTab: React.FC = React.memo(() => {
   const theme = useTheme();
   const { setChapterGeneralSettings, ...settings } =
@@ -182,7 +195,18 @@ const GeneralTab: React.FC = React.memo(() => {
       <List.SubHeader theme={theme}>
         {getString('readerScreen.bottomSheet.navigation')}
       </List.SubHeader>
-      {navigationPreferences.map(renderPreference)}
+      {navigationPreferences.map(item => {
+        if (item.key === 'pageReader') {
+          return (
+            <React.Fragment key={item.key}>
+              {renderPreference(item)}
+              {settings.pageReader &&
+                pagedModePreferences.map(renderPreference)}
+            </React.Fragment>
+          );
+        }
+        return renderPreference(item);
+      })}
     </BottomSheetScrollView>
   );
 });

src/screens/reader/components/WebViewReader.tsx

@@ -374,7 +374,9 @@ const WebViewReader: React.FC<WebViewReaderProps> = ({
             </head>
             <body class="${
               chapterGeneralSettings.pageReader ? 'page-reader' : ''
-            }">
+            } ${
+        chapterGeneralSettings.pageReaderDisableAnimation ? 'no-animation' : ''
+      }">
               <div class="transition-chapter" style="transform: ${
                 isNextChapterScreenVisible
                   ? 'translateX(-100%)'
@@ -437,8 +439,8 @@ const WebViewReader: React.FC<WebViewReaderProps> = ({
     chapter,
     chapterGeneralSettings,
     processedHtml,
-      customJS,
-      customCSS,
+    customJS,
+    customCSS,
     initialReaderSettings,
     novel,
     plugin,
@@ -449,31 +451,31 @@ const WebViewReader: React.FC<WebViewReaderProps> = ({
   ]);
 
   return (
-      <>
-    <WebView
-      ref={webViewRef}
-      onTouchStart={onTouchStart}
-      style={{ backgroundColor: readerSettings.theme }}
-      allowFileAccess={true}
-      originWhitelist={['*']}
-      scalesPageToFit={true}
-      showsVerticalScrollIndicator={false}
-      javaScriptEnabled={true}
-      webviewDebuggingEnabled={__DEV__}
-      onShouldStartLoadWithRequest={({ url }) => {
-        if (isPluginIssueReportUrl(url)) {
-          void Linking.openURL(url);
-          return false;
-        }
-        if (isChapterRefreshUrl(url)) {
-          refetch();
-          return false;
-        }
-        return true;
-      }}
-      onLoadEnd={() => {
-        webViewRef.current?.injectJavaScript(
-          `if (window.reader && window.reader.batteryLevel) {
+    <>
+      <WebView
+        ref={webViewRef}
+        onTouchStart={onTouchStart}
+        style={{ backgroundColor: readerSettings.theme }}
+        allowFileAccess={true}
+        originWhitelist={['*']}
+        scalesPageToFit={true}
+        showsVerticalScrollIndicator={false}
+        javaScriptEnabled={true}
+        webviewDebuggingEnabled={__DEV__}
+        onShouldStartLoadWithRequest={({ url }) => {
+          if (isPluginIssueReportUrl(url)) {
+            void Linking.openURL(url);
+            return false;
+          }
+          if (isChapterRefreshUrl(url)) {
+            refetch();
+            return false;
+          }
+          return true;
+        }}
+        onLoadEnd={() => {
+          webViewRef.current?.injectJavaScript(
+            `if (window.reader && window.reader.batteryLevel) {
             window.reader.batteryLevel.val = ${lastKnownBatteryLevel};
           }`,
           );

src/screens/reader/hooks/__tests__/useChapter.test.ts

@@ -1,6 +1,7 @@
 import { act, renderHook, waitFor } from '@testing-library/react-native';
 import useChapter from '../useChapter';
 import NativeFile from '@modules/native-file';
+import NativeVolumeButtonListener from '@modules/native-volume-button-listener';
 
 const mockUseNovelActions = jest.fn();
 const mockUseChapterGeneralSettings = jest.fn();
@@ -172,6 +173,9 @@ describe('useChapter', () => {
       autoScrollOffset: 100,
       useVolumeButtons: false,
       volumeButtonsOffset: 100,
+      pageReader: false,
+      pageReaderInvertVolumeButtons: false,
+      pageReaderDisableAnimation: false,
     });
     mockUseLibrarySettings.mockReturnValue({ incognitoMode: false });
     mockUseAppSettings.mockReturnValue({
@@ -423,4 +427,108 @@ describe('useChapter', () => {
     expect(result.current.chapter.id).toBe(nextChapter.id);
     expect(result.current.chapterText).toBe('SANITIZED:next body');
   });
+
+  it('injects scripts supporting paged and normal modes when volume buttons are pressed', async () => {
+    const store = createStore();
+    mockUseNovelActions.mockReturnValue(store.state);
+    const mockInjectJavaScript = jest.fn();
+
+    const { result } = renderHook(() =>
+      useChapter(
+        { current: { injectJavaScript: mockInjectJavaScript } as any },
+        initialChapter,
+        novel,
+      ),
+    );
+
+    await waitFor(() =>
+      expect(result.current.chapterContext.loading).toBe(false),
+    );
+
+    const volumeUpCall = (
+      NativeVolumeButtonListener.addListener as jest.Mock
+    ).mock.calls.find(([event]) => event === 'VolumeUp');
+    const volumeDownCall = (
+      NativeVolumeButtonListener.addListener as jest.Mock
+    ).mock.calls.find(([event]) => event === 'VolumeDown');
+
+    expect(volumeUpCall).toBeDefined();
+    expect(volumeDownCall).toBeDefined();
+
+    // Trigger VolumeUp callback
+    volumeUpCall[1]();
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining(
+        'window.pageReader.movePage((window.pageReader.page?.val ?? 0) - 1)',
+      ),
+    );
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining('window.scrollBy'),
+    );
+
+    // Trigger VolumeDown callback
+    volumeDownCall[1]();
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining(
+        'window.pageReader.movePage((window.pageReader.page?.val ?? 0) + 1)',
+      ),
+    );
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining('window.scrollBy'),
+    );
+  });
+
+  it('inverts volume button directions in paged mode when pageReaderInvertVolumeButtons is enabled', async () => {
+    const store = createStore();
+    mockUseNovelActions.mockReturnValue(store.state);
+    mockUseChapterGeneralSettings.mockReturnValue({
+      autoScroll: false,
+      autoScrollInterval: 1,
+      autoScrollOffset: 100,
+      useVolumeButtons: false,
+      volumeButtonsOffset: 100,
+      pageReader: true,
+      pageReaderInvertVolumeButtons: true,
+      pageReaderDisableAnimation: false,
+    });
+    const mockInjectJavaScript = jest.fn();
+
+    const { result } = renderHook(() =>
+      useChapter(
+        { current: { injectJavaScript: mockInjectJavaScript } as any },
+        initialChapter,
+        novel,
+      ),
+    );
+
+    await waitFor(() =>
+      expect(result.current.chapterContext.loading).toBe(false),
+    );
+
+    const volumeUpCall = (
+      NativeVolumeButtonListener.addListener as jest.Mock
+    ).mock.calls.find(([event]) => event === 'VolumeUp');
+    const volumeDownCall = (
+      NativeVolumeButtonListener.addListener as jest.Mock
+    ).mock.calls.find(([event]) => event === 'VolumeDown');
+
+    expect(volumeUpCall).toBeDefined();
+    expect(volumeDownCall).toBeDefined();
+
+    // VolumeUp callback should move +1 (forward) when inverted
+    volumeUpCall[1]();
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining(
+        'window.pageReader.movePage((window.pageReader.page?.val ?? 0) + 1)',
+      ),
+    );
+
+    // VolumeDown callback should move -1 (backward) when inverted
+    volumeDownCall[1]();
+    expect(mockInjectJavaScript).toHaveBeenCalledWith(
+      expect.stringContaining(
+        'window.pageReader.movePage((window.pageReader.page?.val ?? 0) - 1)',
+      ),
+    );
+  });
 });

src/screens/reader/hooks/useChapter.ts

@@ -74,6 +74,8 @@ export default function useChapter(
     autoScrollOffset,
     useVolumeButtons,
     volumeButtonsOffset,
+    pageReader,
+    pageReaderInvertVolumeButtons,
   } = useChapterGeneralSettings();
   const { incognitoMode } = useLibrarySettings();
   const { timeTrackingEnabled, inactivityTimeoutMs } = useAppSettings();
@@ -124,15 +126,32 @@ export default function useChapter(
     Math.round(Dimensions.get('window').height * 0.75),
   );
 
+  const volumeUpDelta = pageReaderInvertVolumeButtons ? 1 : -1;
+  const volumeDownDelta = pageReaderInvertVolumeButtons ? -1 : 1;
+
   useEventListener(NativeVolumeButtonListener, 'VolumeUp', () => {
     webViewRef.current?.injectJavaScript(`(()=>{
-      window.scrollBy({top: -${volumeButtonOffset}, behavior: 'smooth'})
+      const isPaged = ${Boolean(pageReader)};
+      if (isPaged && window.pageReader) {
+        window.pageReader.movePage((window.pageReader.page?.val ?? 0) ${
+          volumeUpDelta >= 0 ? '+' : '-'
+        } 1);
+      } else {
+        window.scrollBy({top: -${volumeButtonOffset}, behavior: 'smooth'});
+      }
     })()`);
   });
 
   useEventListener(NativeVolumeButtonListener, 'VolumeDown', () => {
     webViewRef.current?.injectJavaScript(`(()=>{
-      window.scrollBy({top: ${volumeButtonOffset}, behavior: 'smooth'})
+      const isPaged = ${Boolean(pageReader)};
+      if (isPaged && window.pageReader) {
+        window.pageReader.movePage((window.pageReader.page?.val ?? 0) ${
+          volumeDownDelta >= 0 ? '+' : '-'
+        } 1);
+      } else {
+        window.scrollBy({top: ${volumeButtonOffset}, behavior: 'smooth'});
+      }
     })()`);
   });
 

src/screens/settings/SettingsReaderScreen/tabs/NavigationTab.tsx

@@ -16,6 +16,8 @@ const NavigationTab: React.FC = () => {
     verticalSeekbar = true,
     swipeGestures = false,
     pageReader = false,
+    pageReaderInvertVolumeButtons = false,
+    pageReaderDisableAnimation = false,
     autoScroll = false,
     autoScrollInterval = 10,
     autoScrollOffset = null,
@@ -119,6 +121,38 @@ const NavigationTab: React.FC = () => {
           onPress={() => setChapterGeneralSettings({ pageReader: !pageReader })}
           theme={theme}
         />
+        {pageReader && (
+          <>
+            <SettingSwitch
+              label={getString('readerScreen.bottomSheet.invertVolumeButtons')}
+              description={getString(
+                'readerScreen.bottomSheet.invertVolumeButtonsDescription',
+              )}
+              value={pageReaderInvertVolumeButtons}
+              onPress={() =>
+                setChapterGeneralSettings({
+                  pageReaderInvertVolumeButtons: !pageReaderInvertVolumeButtons,
+                })
+              }
+              theme={theme}
+            />
+            <SettingSwitch
+              label={getString(
+                'readerScreen.bottomSheet.disablePageTransitions',
+              )}
+              description={getString(
+                'readerScreen.bottomSheet.disablePageTransitionsDescription',
+              )}
+              value={pageReaderDisableAnimation}
+              onPress={() =>
+                setChapterGeneralSettings({
+                  pageReaderDisableAnimation: !pageReaderDisableAnimation,
+                })
+              }
+              theme={theme}
+            />
+          </>
+        )}
       </View>
 
       <View style={styles.section}>