Monitors and Screen Resolution

You can extend a remote desktop or published application to multiple monitors. If you have a high-resolution monitor, you can see the remote desktop or published application in full resolution.

Use Multiple Monitors

You can use multiple monitors to display a remote desktop window. This feature is not supported for published applications.

In HTML Access, the multiple-monitor feature extends the remote desktop across multiple monitors but does not provide true independent multi-monitor functionality. Each monitor acts as an extension of a single workspace rather than supporting separate applications per monitor. For full multi-monitor support, use the Horizon Client.

Prerequisites

• You must use HTML Access in a Chrome or Chromium-based Edge browser.
• In your browser settings, verify that the Omnissa Horizon Connection Server site is configured to allow pop-ups.
• You must have two or more monitors.

Procedure

1. Start HTML Access and log in to a server.

2. To enable the multiple-monitor feature, do the following.

   a. Click the Settings toolbar button in the upper-right corner of the desktop and application selector window.

   b. In the Display section of the Settings dialog box, click Set.

   c. If the browser prompts you to grant permission for window placement, select the option to grant this permission.

   Note: If you deny permission for window placement, the browser will display the prompt again for every desktop session. In that case, you must manually grant permission each time to use the multiple-monitor feature.

   d. From the menu, select one of the following display options.

   Option	Description
   Use all displays	Displays the remote desktop on all the monitors connected to the client device.
   Use selected displays	Displays the remote desktop on the monitors that you specify. In the thumbnail preview, select the monitors that you want to use for the display.

   5. After selecting a display option, click OK.
   6. Close the Settings dialog box.

3. If the browser window is in maximized mode, exit maximized mode.

   The multiple-monitor feature does not work if the browser window is maximized. Resize the window before enabling the feature.

4. If you do not already have a desktop session open, in the desktop and application selector window, click the icon for the remote desktop that you want to use.

   Note: When you use the multiple-monitor feature for the first time, the browser might block new windows from opening on the extended monitors. If this problem occurs, click the error prompt in the browser's address bar and select the option to allow new window placement. Then refresh the browser or reconnect to the desktop.

5. If the remote desktop prompts you to grant permission to use full-screen mode, click OK for each monitor in your configuration.

   Note: If the display mode is set to Use selected displays when you add or remove monitors in your configuration, the session reverts to single-monitor mode and displays the desktop in the primary monitor only.

6. To exit from multiple-monitor mode, do the following.

   a. Press and hold the Esc key.

   b. In the Exit the multiple displays mode dialog box, click Yes.

7. To reenter multiple-monitor mode, reload the browser content.The session automatically reenters multiple-monitor mode after a few seconds.

If only one screen is visible despite enabling multiple monitors, ensure that pop-ups are allowed and that the browser is not in full-screen mode.

If the session reverts to a single monitor after adding or removing a monitor, reconfigure the display settings.

What to do next

The multiple-monitor feature supports only one desktop session at a time. To switch to a different desktop, first exit multiple-monitor mode for the current desktop. Then switch to the other desktop and enter multiple-monitor mode.

Use Full-Screen Mode

You can display a remote desktop or published application in full-screen mode.

You cannot use full-screen mode in the following situations.

• You are using multiple monitors.
• The browser is in full-screen mode or is maximized by dragging the mouse.
• You are using Safari.

Prerequisites

Connect to the remote desktop or published application.

Procedure

• To display the remote desktop or published application in full-screen mode, click the Open Menu button at the top of the sidebar and click
• Fullscreen.
• To exit from full-screen mode, click the Open Menu button at the top of the sidebar and click
• Quit fullscreen.Alternatively, press the Esc key. In a Chrome or Chromium Edge browser, press and hold the Esc key.

Setting the Screen Resolution

HTML Access can resize the remote desktop to match the size of the browser window. To use this feature, an administrator must configure the remote desktop to have the correct amount of video RAM (VRAM). The default VRAM configuration is 36 MB. If you are not using 3D applications, the minimum VRAM requirement is 16 MB.

If you use a browser or Chrome device that has a high pixel density resolution, such as a MacBook with Retina Display or a Google Chromebook Pixel, you can set the remote desktop or published application to use that resolution. Turn on the High Resolution Mode option in the Settings window, which is available from the sidebar. This option appears in the

Settings window only if you are using a high-resolution display or a normal display that uses a scale that is greater than 100 percent.

The High Resolution Mode feature cannot change the resolution for an active remote session. You must log out and log in again to make the feature take effect.

To use the 3D rendering feature, an administrator must allocate sufficient VRAM for each remote desktop.

• With the software-accelerated graphics feature, you can use 3D applications, such as Windows Aero themes or Google Earth. This feature requires from 64 MB to 128 MB of VRAM.
• The shared hardware-accelerated graphics feature (vSGA), which is available with vSphere 5.1 or later, enables you to use 3D applications for design, modeling, and multimedia. This feature requires from 64 MB to 512 MB of VRAM. The default is 96 MB.
• The dedicated hardware-accelerated graphics feature (vDGA), which is available with vSphere 5.5 or later, dedicates a single physical GPU (graphical processing unit on an ESXi host to a single virtual machine. Use this feature if you require high-end hardware-accelerated workstation graphics. This feature requires from 64 MB to 512 MB of VRAM. The default is 96 MB.

When 3D rendering is enabled, the maximum number of monitors is one and the maximum resolution is 3840 x 2160.

Similarly, if you use a browser on a device that has a high pixel density resolution, such as a MacBook with Retina Display or a Google Chromebook Pixel, you must allocate sufficient VRAM for each remote desktop.

Important: Estimating the amount of VRAM that you need for the Omnissa Horizon Blast display protocol is similar to estimating how much VRAM is required for the PCoIP display protocol. For more information on estimating the amount of VRAM needed see, Estimating Memory Requirements for Virtual Machine Desktops topic in the Horizon Overview and Deployment Planning guide.

Using DPI Synchronization

The DPI Synchronization feature ensures that the DPI setting in a remote desktop or published application matches the client system's DPI setting.

An administrator can deactivate the DPI synchronization feature.

Like the Display Scaling feature, the DPI Synchronization feature can improve the readability of text and icons on high-DPI displays. Unlike the Display Scaling feature, which increases the size of fonts and images and can make them blurry, the DPI Synchronization feature increases the size of fonts and images, keeping them sharp. For this reason, the DPI Synchronization feature is generally preferred for an optimal user experience.

If DPI synchronization is deactivated, display scaling is used. The Display Scaling feature scales the remote desktop or published application appropriately.

The DPI Synchronization agent group policy setting determines whether the DPI Synchronization feature is activated. The feature is activated by default.

Behavior of DPI Synchronization

The default DPI synchronization behavior depends on the Horizon Agent version that is installed in the agent machine.

Beginning with Horizon Agent 2012, the client's per-monitor DPI setting is synchronized to the agent and changes take effect immediately during a remote session by default. This feature is controlled by the DPI Synchronization Per Monitor agent group policy setting. The DPI Synchronization Per Monitor feature is supported by default for virtual, physical, and RDSH desktops.

With earlier Horizon Agent versions, the client supports synchronization only to the system DPI setting. DPI Synchronization happens during the initial connection, and Display Scaling works in case of reconnection, if necessary. When DPI Synchronization works and the client system's DPI setting matches the remote desktop's DPI setting, Display Scaling cannot take effect, even if you select the Allow Display Scaling option in the user interface. DPI synchronization occurs only when users log in and start a remote session. If users change the DPI setting during a remote session, they must log out and log in again to make the remote desktop's DPI setting match the client system's new DPI setting.

The agent DPI setting is located in the Windows registry at Computer\HKEY_CURRENT_USER\Control Panel\Desktop: logPixels.

Note:

The system DPI setting might not be the same as the main monitor's DPI setting. For example, if you close the main monitor and the system switches to an external display that has a different DPI setting than the main monitor, the system DPI setting is still the same as the DPI setting of the previously closed main monitor.

This version of the client does not support the DPI Synchronization Per Connection agent group policy setting, which is provided with Horizon Agent versions 7.8 through 2006.

For more information about the DPI synchronization group policy settings, see the Horizon Remote Desktop Features and GPOs document for your Horizon Agent version.

Supported Guest Operating Systems for Virtual Desktops

For virtual desktops, the DPI Synchronization feature is supported on the following guest operating systems:

• 32-bit or 64-bit Windows 7
• 32-bit or 64-bit Windows 8.x
• 32-bit or 64-bit Windows 10
• 32-bit or 64-bit Windows 11
• Windows Server 2008 R2 configured as a desktop
• Windows Server 2016 configured as a desktop
• Windows Server 2019 configured as a desktop
• Windows Server 2022 configured as a desktop

Note: For Windows server machines that are configured as a desktop, the DPI Synchronization Per Monitor feature is only supported on Windows Server 2022.

Supported RDS Hosts for Published Desktops and Published Applications

For published desktops and published applications, the DPI Synchronization feature is supported on the following RDS hosts:

• Windows Server 2016
• Windows Server 2019

Tips for Using the DPI Synchronization Feature with HTML Access

Following are tips for using the DPI Synchronization feature.

• Although Windows 10 systems support different DPI settings on different monitors, the DPI Synchronization feature uses the DPI value that is set on the client system's monitor in which the web browser used for launching the HTML Access client session is located. HTML Access does not support different DPI settings in different monitors.
• To sync up with another monitor that has a different DPI setting, you must log out of the remote desktop or published application, drag the web browser used for launching the HTML Access client session to the other monitor, and log back in to the remote desktop or published application to make the DPI settings match between the client system and remote desktop or published application.
• If you want to set the resolution manually, you might be able to activate the High Resolution Mode setting. For information, see "Setting the Screen Resolution for Remote Desktops and Published Applications".