diff --git a/docs/src/api/class-route.md b/docs/src/api/class-route.md
index 139d7e95ff9a0..8b60f563a56c2 100644
--- a/docs/src/api/class-route.md
+++ b/docs/src/api/class-route.md
@@ -112,10 +112,18 @@ If set changes the request method (e.g. GET or POST)
 
 ### option: Route.continue.postData
 * since: v1.8
+* langs: js, python, java
 - `postData` <[string]|[Buffer]>
 
 If set changes the post data of request
 
+### option: Route.continue.postData
+* since: v1.8
+* langs: csharp
+- `postData` <[Buffer]>
+
+If set changes the post data of request
+
 ### option: Route.continue.headers
 * since: v1.8
 - `headers` <[Object]<[string], [string]>>
@@ -378,10 +386,18 @@ If set changes the request method (e.g. GET or POST)
 
 ### option: Route.fallback.postData
 * since: v1.23
+* langs: js, python, java
 - `postData` <[string]|[Buffer]>
 
 If set changes the post data of request
 
+### option: Route.fallback.postData
+* since: v1.23
+* langs: csharp
+- `postData` <[Buffer]>
+
+If set changes the post data of request
+
 ### option: Route.fallback.headers
 * since: v1.23
 - `headers` <[Object]<[string], [string]>>
diff --git a/docs/src/chrome-extensions-js-python.md b/docs/src/chrome-extensions-js-python.md
index 04a84f56cc9e2..648d4b3b8574e 100644
--- a/docs/src/chrome-extensions-js-python.md
+++ b/docs/src/chrome-extensions-js-python.md
@@ -103,8 +103,8 @@ First, add fixtures that will load the extension:
 
 ```ts
 // fixtures.ts
-import { test as base, expect, chromium, type BrowserContext } from "@playwright/test";
-import path from "path";
+import { test as base, expect, chromium, type BrowserContext } from '@playwright/test';
+import path from 'path';
 
 export const test = base.extend<{
   context: BrowserContext;
@@ -185,16 +185,16 @@ def extension_id(context) -> Generator[str, None, None]:
 Then use these fixtures in a test:
 
 ```ts
-import { test, expect } from "./fixtures";
+import { test, expect } from './fixtures';
 
-test("example test", async ({ page }) => {
-  await page.goto("https://example.com");
-  await expect(page.locator("body")).toHaveText("Changed by my-extension");
+test('example test', async ({ page }) => {
+  await page.goto('https://example.com');
+  await expect(page.locator('body')).toHaveText('Changed by my-extension');
 });
 
-test("popup page", async ({ page, extensionId }) => {
+test('popup page', async ({ page, extensionId }) => {
   await page.goto(`chrome-extension://${extensionId}/popup.html`);
-  await expect(page.locator("body")).toHaveText("my-extension popup");
+  await expect(page.locator('body')).toHaveText('my-extension popup');
 });
 ```
 
diff --git a/utils/doclint/documentation.js b/utils/doclint/documentation.js
index d912cdd4ad865..fa0f867c11937 100644
--- a/utils/doclint/documentation.js
+++ b/utils/doclint/documentation.js
@@ -59,6 +59,12 @@ const md = require('../markdown');
  * }} Metainfo
  */
 
+/**
+ * @typedef {{
+ *   csharpOptionOverloadsShortNotation?: boolean,
+ * }} LanguageOptions
+ */
+
 class Documentation {
   /**
    * @param {!Array<!Documentation.Class>} classesArray
@@ -104,13 +110,14 @@ class Documentation {
 
   /**
    * @param {string} lang
+   * @param {LanguageOptions=} options
    */
-  filterForLanguage(lang) {
+  filterForLanguage(lang, options = {}) {
     const classesArray = [];
     for (const clazz of this.classesArray) {
       if (clazz.langs.only && !clazz.langs.only.includes(lang))
         continue;
-      clazz.filterForLanguage(lang);
+      clazz.filterForLanguage(lang, options);
       classesArray.push(clazz);
     }
     this.classesArray = classesArray;
@@ -259,13 +266,14 @@ Documentation.Class = class {
 
   /**
    * @param {string} lang
+   * @param {LanguageOptions=} options
    */
-  filterForLanguage(lang) {
+  filterForLanguage(lang, options = {}) {
     const membersArray = [];
     for (const member of this.membersArray) {
       if (member.langs.only && !member.langs.only.includes(lang))
         continue;
-      member.filterForLanguage(lang);
+      member.filterForLanguage(lang, options);
       membersArray.push(member);
     }
     this.membersArray = membersArray;
@@ -406,31 +414,41 @@ Documentation.Member = class {
     }
   }
 
-    /**
+  /**
    * @param {string} lang
+   * @param {LanguageOptions=} options
    */
-  filterForLanguage(lang) {
+  filterForLanguage(lang, options = {}) {
     if (!this.type)
       return;
     if (this.langs.aliases && this.langs.aliases[lang])
       this.alias = this.langs.aliases[lang];
     if (this.langs.types && this.langs.types[lang])
       this.type = this.langs.types[lang];
-    this.type.filterForLanguage(lang);
+    this.type.filterForLanguage(lang, options);
     const argsArray = [];
     for (const arg of this.argsArray) {
       if (arg.langs.only && !arg.langs.only.includes(lang))
         continue;
       const overriddenArg = (arg.langs.overrides && arg.langs.overrides[lang]) || arg;
-      overriddenArg.filterForLanguage(lang);
+      overriddenArg.filterForLanguage(lang, options);
       // @ts-ignore
       if (overriddenArg.name === 'options' && !overriddenArg.type.properties.length)
         continue;
       // @ts-ignore
-      overriddenArg.type.filterForLanguage(lang);
+      overriddenArg.type.filterForLanguage(lang, options);
       argsArray.push(overriddenArg);
     }
     this.argsArray = argsArray;
+
+    const optionsArg = this.argsArray.find(arg => arg.name === 'options');
+    if (lang === 'csharp' && optionsArg) {
+      try {
+        patchCSharpOptionOverloads(optionsArg, options);
+      } catch (e) {
+        throw new Error(`Error processing csharp options in ${this.clazz?.name}.${this.name}: ` + e.message);
+      }
+    }
   }
 
   filterOutExperimental() {
@@ -642,15 +660,16 @@ Documentation.Type = class {
 
   /**
    * @param {string} lang
+   * @param {LanguageOptions=} options
    */
-  filterForLanguage(lang) {
+  filterForLanguage(lang, options = {}) {
     if (!this.properties)
       return;
     const properties = [];
     for (const prop of this.properties) {
       if (prop.langs.only && !prop.langs.only.includes(lang))
         continue;
-      prop.filterForLanguage(lang);
+      prop.filterForLanguage(lang, options);
       properties.push(prop);
     }
     this.properties = properties;
@@ -839,4 +858,73 @@ function generateSourceCodeComment(spec) {
   return md.render(comments, 120);
 }
 
+/**
+ * @param {Documentation.Member} optionsArg
+ * @param {LanguageOptions=} options
+ */
+function patchCSharpOptionOverloads(optionsArg, options = {}) {
+  const props = optionsArg.type?.properties;
+  if (!props)
+    return;
+  const propsToDelete = new Set();
+  const propsToAdd = [];
+  for (const prop of props) {
+    const union = prop.type?.union;
+    if (!union)
+      continue;
+    const isEnum = union[0].name.startsWith('"');
+    const isNullable = union.length === 2 && union.some(type => type.name === 'null');
+    if (isEnum || isNullable)
+      continue;
+
+    const shortNotation = [];
+    propsToDelete.add(prop);
+    for (const type of union) {
+      const suffix = csharpOptionOverloadSuffix(prop.name, type.name);
+      if (options.csharpOptionOverloadsShortNotation) {
+        if (type.name === 'string')
+          shortNotation.push(prop.alias);
+        else
+          shortNotation.push(prop.alias + suffix);
+        continue;
+      }
+
+      const newProp = prop.clone();
+      newProp.name = prop.name + suffix;
+      newProp.alias = prop.alias + suffix;
+      newProp.type = type;
+      propsToAdd.push(newProp);
+
+      if (type.name === 'string') {
+        const stringProp = prop.clone();
+        stringProp.type = type;
+        propsToAdd.push(stringProp);
+      }
+    }
+    if (options.csharpOptionOverloadsShortNotation) {
+      const newProp = prop.clone();
+      newProp.alias = newProp.name = shortNotation.join('|');
+      propsToAdd.push(newProp);
+    }
+  }
+  for (const prop of propsToDelete)
+    props.splice(props.indexOf(prop), 1);
+  props.push(...propsToAdd);
+}
+
+/**
+ * @param {string} option
+ * @param {string} type
+ */
+function csharpOptionOverloadSuffix(option, type) {
+  switch (type) {
+    case 'string': return 'String';
+    case 'RegExp': return 'Regex';
+    case 'function': return 'Func';
+    case 'Buffer': return 'Byte';
+    case 'Serializable': return 'Object';
+  }
+  throw new Error(`CSharp option "${option}" has unsupported type overload "${type}"`);
+}
+
 module.exports = Documentation;
diff --git a/utils/doclint/generateDotnetApi.js b/utils/doclint/generateDotnetApi.js
index 8dc7c3460e4b3..cc39a7cd9ff84 100644
--- a/utils/doclint/generateDotnetApi.js
+++ b/utils/doclint/generateDotnetApi.js
@@ -287,7 +287,7 @@ function renderConstructors(name, type, out) {
 function renderMember(member, parent, options, out) {
   const name = toMemberName(member);
   if (member.kind === 'method') {
-    renderMethod(member, parent, name, { mode: 'options', trimRunAndPrefix: options.trimRunAndPrefix }, out);
+    renderMethod(member, parent, name, { trimRunAndPrefix: options.trimRunAndPrefix }, out);
     return;
   }
 
@@ -348,12 +348,6 @@ function getPropertyOverloads(type, member, name, parent) {
     if (member.type.expression === '[string]|[float]')
       jsonName = `${member.name}String`;
     overloads.push({ type, name, jsonName });
-  } else {
-    for (const overload of member.type.union) {
-      const t = translateType(overload, parent, t => generateNameDefault(member, name, t, parent));
-      const suffix = toOverloadSuffix(t);
-      overloads.push({ type: t, name: name + suffix, jsonName: member.name + suffix });
-    }
   }
   return overloads;
 }
@@ -463,7 +457,6 @@ function generateEnumNameIfApplicable(type) {
  * @param {Documentation.Class | Documentation.Type} parent
  * @param {string} name
  * @param {{
- *   mode: 'options'|'named'|'base',
  *   nodocs?: boolean,
  *   abstract?: boolean,
  *   public?: boolean,
@@ -556,16 +549,12 @@ function renderMethod(member, parent, name, options, out) {
       return;
 
     if (arg.name === 'options') {
-      if (options.mode === 'options' || options.mode === 'base') {
-        const optionsType = rewriteSuggestedOptionsName(member.clazz.name + name.replace('<T>', '') + 'Options');
-        if (!optionTypes.has(optionsType) || arg.type.properties.length > optionTypes.get(optionsType).properties.length)
-          optionTypes.set(optionsType, arg.type);
-        args.push(`${optionsType}? options = default`);
-        argTypeMap.set(`${optionsType}? options = default`, 'options');
-        addParamsDoc('options', ['Call options']);
-      } else {
-        arg.type.properties.forEach(processArg);
-      }
+      const optionsType = rewriteSuggestedOptionsName(member.clazz.name + name.replace('<T>', '') + 'Options');
+      if (!optionTypes.has(optionsType) || arg.type.properties.length > optionTypes.get(optionsType).properties.length)
+        optionTypes.set(optionsType, arg.type);
+      args.push(`${optionsType}? options = default`);
+      argTypeMap.set(`${optionsType}? options = default`, 'options');
+      addParamsDoc('options', ['Call options']);
       return;
     }
 
@@ -632,37 +621,6 @@ function renderMethod(member, parent, name, options, out) {
       .sort((a, b) => b.alias === 'options' ? -1 : 0) // move options to the back to the arguments list
       .forEach(processArg);
 
-  let body = ';';
-  if (options.mode === 'base') {
-    // Generate options -> named transition.
-    const tokens = [];
-    for (const arg of member.argsArray) {
-      if (arg.name === 'action' && options.trimRunAndPrefix)
-        continue;
-      if (arg.name !== 'options') {
-        tokens.push(toArgumentName(arg.name));
-        continue;
-      }
-      for (const opt of arg.type.properties) {
-        // TODO: use translate type here?
-        if (opt.type.union && !opt.type.union[0].name.startsWith('"') && opt.type.union[0].name !== 'null' && opt.type.expression !== '[string]|[Buffer]') {
-          // Explode overloads.
-          for (const t of opt.type.union) {
-            const suffix = toOverloadSuffix(translateType(t, parent));
-            tokens.push(`${opt.name}${suffix}: options.${toMemberName(opt)}${suffix}`);
-          }
-        } else {
-          tokens.push(`${opt.alias || opt.name}: options.${toMemberName(opt)}`);
-        }
-      }
-    }
-    body = `
-{
-    options ??= new ${member.clazz.name}${name}Options();
-    return ${toAsync(name, member.async)}(${tokens.join(', ')});
-}`;
-  }
-
   if (!explodedArgs.length) {
     if (!options.nodocs) {
       out.push(...XmlDoc.renderXmlDoc(member.spec, maxDocumentationColumnWidth));
@@ -670,7 +628,7 @@ function renderMethod(member, parent, name, options, out) {
     }
     if (member.deprecated)
       out.push(`[System.Obsolete]`);
-    out.push(`${modifiers}${type} ${toAsync(name, member.async)}(${args.join(', ')})${body}`);
+    out.push(`${modifiers}${type} ${toAsync(name, member.async)}(${args.join(', ')});`);
   } else {
     let containsOptionalExplodedArgs = false;
     explodedArgs.forEach((explodedArg, argIndex) => {
@@ -692,7 +650,7 @@ function renderMethod(member, parent, name, options, out) {
           overloadedArgs.push(arg);
         }
       }
-      out.push(`${modifiers}${type} ${toAsync(name, member.async)}(${overloadedArgs.join(', ')})${body}`);
+      out.push(`${modifiers}${type} ${toAsync(name, member.async)}(${overloadedArgs.join(', ')});`);
       if (argIndex < explodedArgs.length - 1)
         out.push(''); // output a special blank line
     });
@@ -712,7 +670,7 @@ function renderMethod(member, parent, name, options, out) {
         if (!options.nodocs)
           printArgDoc(argType, paramDocs.get(argType), out);
       });
-      out.push(`${type} ${name}(${filteredArgs.join(', ')})${body}`);
+      out.push(`${type} ${name}(${filteredArgs.join(', ')});`);
     }
   }
 }
@@ -874,14 +832,6 @@ function printArgDoc(name, value, out) {
   }
 }
 
-/**
- * @param {string} typeName
- * @return {string}
- */
-function toOverloadSuffix(typeName) {
-  return toTitleCase(typeName.replace(/[<].*[>]/, '').replace(/[^a-zA-Z]/g, ''));
-}
-
 /**
  * @param {string} name
  * @param {boolean} convert
@@ -895,7 +845,7 @@ function toAsync(name, convert) {
 }
 
 /**
- * @param {string} suggestedName 
+ * @param {string} suggestedName
  * @returns {string}
  */
 function rewriteSuggestedOptionsName(suggestedName) {