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Customize the Chromium Browser options

In HTML Executable, choose Application Settings => Rendering Engine.

A lot of Chromium options can be configured there.

AdditionalChromiumArgs

Lets you add some custom Chromium command-line arguments. For example, if you want to disable the GPU accelerated video display, add `--disable-accelerated-video`. To add multiple arguments, separate each two arguments by space.

AllowOutdatedPlugins

The Chromium engine has a security feature that does not allow users to run any outdated plugins inside the web browser. You can disable it with this property. Please note that allowing the use of outdated plugins exposes your users to security vulnerabilities of those plugins.

ApplicationCache

Controls whether the application cache can be used.

AutoOpenExtensions

Allows a compiled file within the eBook or application to be opened in its dedicated application when the associated link is visited by the end user. HTML Executable determines this behavior based on the file extension; if the file extension is included in the list for this property, then the file will be directly opened in its dedicated application.

Please note that this action temporarily extracts the file onto the user's hard drive, making it potentially vulnerable to unauthorized copying. Therefore, it is essential to consider the security aspects before using this property.

The list of extensions in the AutoOpenExtensions property should be separated by semicolons. For example, if you want to open .docx and .xlsx files in their dedicated applications, the property value should be set as .Docx;.xlsx.

BackgroundColor

Opaque background color used for the browser before a document is loaded and when no document color is specified.Only the RGB components of the specified value will be used. The alpha component must greater than 0 to enable use of the background color but will be otherwise ignored.

CaretBrowsing

Controls whether the caret position will be drawn.

Custom404Error

Indicates whether the custom error page defined in Dialog Boxes should be used to display missing pages (404 file not found). If True, a 200 OK status will be returned to the web browser. If False, a 404 error will be returned to the web browser and the standard 404 error page will be shown.

CustomUserAgent

Lets you specify a custom User-Agent for the web browser.

Databases

Controls whether databases can be used.

DefLocale

Defines which locale (language) should be used by the Chromium engine (useful for localization of default buttons for instance). List of values are available in the `CEFRuntime\locales` subfolder of the HTML Executable's location.

For instance, to use the French locale, enter `fr`.

DeveloperTools

Indicates whether Chomium Developer Tools should be enabled or not. End users can access these tools with the context-menu of the internal browser.

DisableAccelerated2DCanvas

Controls whether accelerated 2D canvas can be used.

DisableAlertDialogWorkaround

Disables the status bar flicker (if the bar is hidden) related to JavaScript dialog box workaround.

DisableDragDrop

Controls whether drag/drop of external resources is allowed or not.

DisableFindText

Lets you disable the "Find Text" menu command.

DisableImgDragDrop

Lets you disable the drag/drop feature for images. For instance, if the end user drags and drops an image onto Windows Explorer, the Chromium engine will save the image as a file into the folder. It's a possible leak for your compiled image files. So, to avoid this leak, activate this property.

DisableLocalCache

Allows your application and Chromium engine to store cache and temporary files onto the end user's computer. By default, it will be a subfolder in the User Data directory as explained here.

DisableSafeBrowsing

Lets you disable the use of the Google Safe Browsing service in your application.

DoNotTrack

Lets you enable/disable the Do Not Track feature of the web browser.

EnableGPUPlugin

Controls whether GPUplugins can be used. Should be left off!

EnableMediaStream

Controls whether WebRTC is handled or not. Note that, for correct WebRTC support, use of the secure protocol https is recommended. Thus, do not enable the "Do not use secure HTTPS for internal protocol" option.

EnableSpeechInput

Controls whether speech input API can be used.

FileAccessFromFileUrls

Controls whether file URLs will have access to all URLs.

ForbidDownloadMimeType

Prevents downloads of internal resources (for instance, on default video player).

The Chromium engine allows end users to download a played video (or audio) resource using the context menu. If you cannot disable this menu from HTML, it is still possible to prevent the download of the audio or video file using this option.

For instance, if you enter `audio/mp3;audio/ogg`, HTML Executable will prevent .MP3 and .OGG files from being downloaded, but not played back by the video or audio player.

ImageLoading

Allows images or not.

ImageShrinkStandaloneToFit

How images are resized.

Javascript

Allows JS execution or not.

JavascriptAccessClipboard, JavascriptCloseWindows, JavascriptDomPaste, JavascriptOpenWindows

Customize JS permissions

LocalStorage

Allow LocalStorage or not

LogSeverity

Enable Chromium debugging log or not:

•Default logging (currently INFO logging) `LOGSEVERITY_DEFAULT`

•Verbose logging: `LOGSEVERITY_VERBOSE`

•INFO logging: `LOGSEVERITY_INFO`

•WARNING logging: `LOGSEVERITY_WARNING`,

•ERROR logging: `LOGSEVERITY_ERROR`,

•Disables logging completely: `LOGSEVERITY_DISABLE` (default in ExeOutput for PHP)

If enabled, the Chromium log file is then stored in the same folder as the application .EXE file and with the filename: `cefdebug.log`
Ensure that the folder is writable if you want the log to be available.

MultiThreadingMode

If you're experiencing problems displaying certain resources or need to refresh a page to display all the images, for example, you can try modifying the multi-threading mode used by HTML Executable to read files in the HTML rendering engine or even disable multithreading with this property. However, this can cause your ebook application to be less responsive.

MuteAudio

If enabled, no audio will be played.

PersistSessionCookies

To allow session cookies (cookies without an expiry date or validity interval) to persist next time the application is run. Session cookies are generally intended to be transient and most Web browsers do not persist them.

Plugins

Allows Plugins or not.

SendReferrer

Should the web browser include the referrer into the HTTP headers.

TabToLinks

Controls whether the tab key can advance focus to links.

TextAreaResize

Controls whether text areas can be resized.

UniversalAccessFromFileUrls

Controls whether file URLs will have access to all URLs.

Webgl

Allows Webgl or not.

WebSecurity

Controls whether web security restrictions (same-origin policy) will be enforced. Disabling this setting is not recommend as it will allow risky/ security behavior such as cross-site scripting (XSS).

WindowlessFrameRate

Ignored.

Please refer to the wiki of the CEF3 project for further explanation.