add FAQ section in README based on some common issues

README.md

@@ -131,6 +131,76 @@ English   |   [Indonesia](README_IN.md)   | &
 
 </div>
 
+## Frequently Asked Questions (FAQ)
+
+This FAQ summarizes common issues encountered by ChatGPT Box users and provides
+suggested solutions based on discussions in the GitHub Issues section.
+
+If you still haven't found what you're looking for, please submit an [Issue](https://github.com/josStorer/chatGPTBox/issues).
+
+### Cannot log in to ChatGPT.com with this extension active using Brave
+
+Related issue: [#794](https://github.com/josStorer/chatGPTBox/issues/794)
+
+Users may encounter "something went wrong" with the ChatGPT Box extension enabled.
+
+**Possible causes:**
+
+- The extension modifies some network requests or page content, which may
+  interfere with the ChatGPT.com login flow.
+- Brave browser’s built-in privacy protections (shields, blocking scripts or
+  cookies) may conflict with the extension.
+
+**Solution:**
+
+1. Disable the extension.
+2. Log in.
+3. Re-enable it.
+
+Note: This issue remains unresolved.
+
+### Google Gemini not working
+
+Related issues: [#786](https://github.com/josStorer/chatGPTBox/issues/786), [#757](https://github.com/josStorer/chatGPTBox/issues/757)
+
+Gemini may work intermittently.
+
+Note: This issue remains unresolved.
+
+**Possible causes:**
+
+- Google Gemini’s web interface/API may have changed or is unstable.
+- The ChatGPTBox extension’s current integration with Gemini is incomplete or experimental.
+- Authentication or session handling is inconsistent.
+- Gemini may block access depending on region or account type.
+
+**Possible solutions:**
+
+- Try refreshing the page or restarting the browser.
+- Try logging out of Google and logging in again.
+- Check if there is an updated version of the extension — newer versions may fix
+  compatibility issues.
+
+### Bilibili not working correctly
+
+Related issues: [#732](https://github.com/josStorer/chatGPTBox/issues/732), [#703](https://github.com/josStorer/chatGPTBox/issues/703)
+
+**Possible causes:**
+
+- Bilibili uses dynamic page loading (SPA) and complex DOM structure, which may
+  interfere with the extension’s side panel injection.
+- The site may block iframe embedding or restrict third-party scripts.
+- Bilibili’s CSS appears to override the Markdown styles used by the extension.
+- Conflicts with Bilibili’s own content scripts or other extensions.
+- Extension may not detect the correct text input areas on the site.
+
+**Possible solutions:**
+
+- Try enabling floating window mode in ChatGPTBox settings. This works better on
+  sites that block side panels.
+- Test on different pages, such as video pages, the homepage, and comments.
+- Try disabling other extensions that interact with Bilibili.
+
 ## Credit
 
 This project is based on one of my other repositories, [josStorer/chatGPT-search-engine-extension](https://github.com/josStorer/chatGPT-search-engine-extension)