[Tabs] Fix not scrolling to correct tab after refresh when auto scrollable

packages/mui-material/src/Tabs/Tabs.js

@@ -634,7 +634,8 @@ const Tabs = React.forwardRef(function Tabs(inProps, ref) {
       scroll(nextScrollStart, { animation });
     } else if (tabMeta[end] > tabsMeta[end]) {
       // right side of button is out of view
-      const nextScrollStart = tabsMeta[scrollStart] + (tabMeta[end] - tabsMeta[end]);
+      const nextScrollStart =
+        tabsMeta[scrollStart] + (tabMeta[end] - tabsMeta[end]) + tabMeta[size];
       scroll(nextScrollStart, { animation });
     }
   });

test/regressions/fixtures/Tabs/LTRHorizontalTabs.js

@@ -0,0 +1,32 @@
+import * as React from 'react';
+import Box from '@mui/material/Box';
+import Tabs from '@mui/material/Tabs';
+import Tab from '@mui/material/Tab';
+
+export default function LTRHorizontalTabs() {
+  const [value, setValue] = React.useState(4);
+
+  const handleChange = (event, newValue) => {
+    setValue(newValue);
+  };
+  return (
+    <Box sx={{ width: 300, display: 'flex' }}>
+      <Tabs
+        value={value}
+        variant="scrollable"
+        scrollButtons
+        orientation="horizontal"
+        onChange={handleChange}
+        aria-label="scrollable auto tabs example"
+      >
+        <Tab label="Tab A" />
+        <Tab label="Tab B" />
+        <Tab label="Tab C" />
+        <Tab label="Tab D" />
+        <Tab label="Tab E" />
+        <Tab label="Tab F" />
+        <Tab label="Tab G" />
+      </Tabs>
+    </Box>
+  );
+}

test/regressions/fixtures/Tabs/LTRVerticalTabs.js

@@ -0,0 +1,32 @@
+import * as React from 'react';
+import Box from '@mui/material/Box';
+import Tabs from '@mui/material/Tabs';
+import Tab from '@mui/material/Tab';
+
+export default function LTRVerticalTabs() {
+  const [value, setValue] = React.useState(4);
+
+  const handleChange = (event, newValue) => {
+    setValue(newValue);
+  };
+  return (
+    <Box sx={{ height: 200, display: 'flex' }}>
+      <Tabs
+        value={value}
+        variant="scrollable"
+        scrollButtons
+        orientation="vertical"
+        onChange={handleChange}
+        aria-label="scrollable auto tabs example"
+      >
+        <Tab label="Tab A" />
+        <Tab label="Tab B" />
+        <Tab label="Tab C" />
+        <Tab label="Tab D" />
+        <Tab label="Tab E" />
+        <Tab label="Tab F" />
+        <Tab label="Tab G" />
+      </Tabs>
+    </Box>
+  );
+}

test/regressions/fixtures/Tabs/RTLHorizontalTabs.js

@@ -0,0 +1,38 @@
+import * as React from 'react';
+import { prefixer } from 'stylis';
+import rtlPlugin from '@mui/stylis-plugin-rtl';
+import { CacheProvider } from '@emotion/react';
+import createCache from '@emotion/cache';
+import { StyleSheetManager } from 'styled-components';
+import { ThemeProvider, createTheme } from '@mui/material/styles';
+import Box from '@mui/material/Box';
+import Tabs from '@mui/material/Tabs';
+import Tab from '@mui/material/Tab';
+
+// Create rtl cache
+const cacheRtl = createCache({
+  key: 'muirtl',
+  stylisPlugins: [prefixer, rtlPlugin],
+});
+
+export default function RTLHorizontalTabs() {
+  return (
+    <StyleSheetManager stylisPlugins={[rtlPlugin]}>
+      <CacheProvider value={cacheRtl}>
+        <ThemeProvider theme={createTheme({ direction: 'rtl' })}>
+          <Box dir="rtl" sx={{ width: 300, display: 'flex' }}>
+            <Tabs value={2} variant="scrollable" scrollButtons orientation="horizontal">
+              <Tab label="Tab A" />
+              <Tab label="Tab B" />
+              <Tab label="Tab C" />
+              <Tab label="Tab D" />
+              <Tab label="Tab E" />
+              <Tab label="Tab F" />
+              <Tab label="Tab G" />
+            </Tabs>
+          </Box>
+        </ThemeProvider>
+      </CacheProvider>
+    </StyleSheetManager>
+  );
+}