NVDA Screen Curtain: Should Temporary Mode Be Removed?

Navigating the digital world can be challenging for visually impaired users, and screen readers like NVDA (NonVisual Desktop Access) play a crucial role in providing access to information. One of NVDA's features, the screen curtain, enhances privacy by blacking out the display, allowing users to work without exposing their screen content to others. However, the current implementation of the screen curtain, particularly its temporary mode, has sparked debate within the NVDA community. This article delves into the discussion surrounding the removal of the temporary screen curtain mode, exploring the problems it poses, potential solutions, and alternatives.

Understanding the Current Screen Curtain Implementation

The screen curtain in NVDA is designed to provide privacy by making the screen black, preventing others from viewing the content being accessed. Currently, NVDA offers two modes for the screen curtain: temporary and persistent. The temporary mode allows users to enable the screen curtain for a single session, while the persistent mode keeps the screen curtain active across multiple sessions. This dual-mode system, combined with the "Save configuration when exiting NVDA" option, introduces complexities that can lead to a suboptimal user experience. To fully appreciate the discussion surrounding the screen curtain, it’s essential to grasp the intricacies of its current functionality. The temporary mode, in theory, offers a quick way to activate the screen curtain without permanently altering the settings. However, the interaction between this mode and the configuration-saving feature creates a potentially confusing scenario for users. For example, enabling the temporary screen curtain with the “Save configuration” option turned on can lead to unexpected behavior, as the user might assume the setting will not persist across sessions.

The persistent mode, on the other hand, is designed for users who consistently require the screen curtain for privacy. While straightforward in its intent, the persistent mode also presents challenges when combined with the configuration-saving option. If a user disables the screen curtain in persistent mode but has the “Save configuration” option disabled, they might find the screen curtain re-enabled in the next session, leading to frustration and a sense of unpredictability. The core issue lies in the dual nature of the screen curtain modes and their interaction with the global configuration settings. This complexity not only makes it difficult for users to understand and manage the screen curtain but also adds to the cognitive load, potentially detracting from their overall experience. Streamlining this functionality could significantly enhance the usability of NVDA, making it more intuitive and user-friendly for both new and experienced users.

The Problems with the Temporary Screen Curtain Mode

The current implementation of the temporary screen curtain mode in NVDA presents several challenges. One of the primary issues is the complex user experience (UX) resulting from the existence of two modes (temporary and persistent) combined with the "Save configuration when exiting NVDA" option. This combination creates a matrix of possibilities that can be confusing for users to navigate. The user experience is further complicated by the fact that enabling the temporary screen curtain with the "Save configuration when exiting NVDA" option turned on can have a similar effect to enabling the permanent screen curtain with the same option turned off. This overlap in functionality can lead to user confusion and make it difficult to predict the behavior of the screen curtain. For instance, a user might intend to use the screen curtain temporarily but inadvertently save the configuration, resulting in the screen curtain being enabled in subsequent sessions. Conversely, a user might want the screen curtain to be permanently enabled but forget to save the configuration, leading to the screen curtain being disabled the next time they use NVDA.

Another significant problem arises from the interaction sequence required to toggle the screen curtain. If a user accidentally enables the screen curtain, they cannot immediately disable it because the double-press action enables it permanently. Similarly, if the screen curtain is permanently enabled and a user accidentally disables it, they cannot re-enable it with a single press. This unintuitive behavior can be frustrating, especially in situations where quick adjustments are necessary. Imagine a scenario where a user is in a public setting and accidentally enables the screen curtain. The inability to quickly disable it could lead to anxiety and disrupt their workflow. The reverse situation is equally problematic. If a user inadvertently disables the screen curtain when they intended to keep it active, the extra steps required to re-enable it can be time-consuming and disruptive.

Beyond the UX issues, the underlying code for the temporary mode is considered complex and difficult to maintain. This complexity not only makes it harder to fix bugs and implement new features but also increases the risk of introducing new issues. The technical debt associated with the temporary mode code can hinder the overall development and stability of NVDA, diverting resources from other important areas. From a maintainability perspective, simplifying the screen curtain functionality would likely reduce the codebase's complexity, making it easier for developers to understand, modify, and debug. This, in turn, can lead to a more robust and efficient screen reader, ultimately benefiting the users.

Proposed Solution: Removing the Temporary Mode

To address these issues, a proposed solution involves streamlining the screen curtain functionality by removing the temporary mode altogether. This would simplify the user experience and reduce the complexity of the underlying code. By eliminating the distinction between temporary and persistent modes, the screen curtain would function as a simple on/off toggle, making it easier for users to understand and control. The core of this solution lies in the idea of simplifying the user interface and reducing the cognitive load associated with managing the screen curtain. With a single on/off toggle, users would no longer need to worry about the nuances of temporary versus persistent settings, leading to a more intuitive and predictable experience.

In conjunction with this change, the "Make screen black (immediate effect)" checkbox would also be removed. This checkbox currently allows users to toggle the screen curtain directly from the settings dialog, but its removal would ensure that enabling or disabling the screen curtain is done exclusively through the designated gesture. This consistency in interaction can further enhance the user experience by establishing a clear and unified method for controlling the screen curtain. The rationale behind this decision is to promote a more streamlined workflow. By relying solely on the gesture, users can quickly toggle the screen curtain without having to navigate through the settings menu, making the process more efficient and less disruptive.

To accommodate users who prefer to have the screen curtain enabled automatically at startup, a new checkbox would be added to the screen curtain settings group: "Enable screen curtain when NVDA starts." This option would allow users to configure NVDA to launch with the screen curtain already active, catering to those who prioritize privacy from the moment they start their computer. This addition is crucial for ensuring that the proposed changes do not negatively impact users who have come to rely on the screen curtain being enabled by default. The new checkbox provides a clear and straightforward way for these users to maintain their preferred configuration, ensuring a smooth transition to the simplified screen curtain functionality. The absence of a toggle gesture associated with this checkbox is intentional, as its primary purpose is to control the screen curtain state at startup, rather than during a session. This distinction helps to maintain the simplicity of the in-session controls while still accommodating users' preferences for the initial state of the screen curtain.

This proposed solution aims to strike a balance between different approaches to screen curtain functionality. It avoids the complete lack of memorization of startup state seen in JAWS while also differing from TalkBack's model, which persists the state between sessions without offering per-session control. This compromise seeks to provide a flexible and user-friendly experience that meets the needs of a diverse range of users. The underlying philosophy is to prioritize simplicity and predictability while still offering the essential functionality that users expect from a screen curtain. By carefully considering the strengths and weaknesses of existing implementations in other screen readers, this solution aims to create a screen curtain experience that is both intuitive and effective.

Alternatives Considered

While removing the temporary mode is the preferred solution, alternative approaches have also been considered. One alternative is to implement only the first point of the proposed solution, which involves removing the temporary mode but leaving the rest of the current implementation intact. This would result in a TalkBack-like screen curtain, where a new session starts with the screen curtain in the same state (enabled/disabled) as it was when the previous session was terminated. This approach would simplify the UX to some extent but would not address the complexities associated with the "Make screen black (immediate effect)" checkbox or the underlying code. While this alternative offers a partial solution, it falls short of fully addressing the core issues with the current implementation. The persistence of the screen curtain state between sessions, without the option for per-session control, might not be suitable for all users, particularly those who prefer to have more flexibility in managing their privacy settings.

Another alternative is to leave the screen feature as is and observe how users interact with it following the recent changes, such as the migration to the privacy panel and the removal of profile-specific settings. This approach would allow the NVDA development team to gather data on real-world usage patterns and identify any remaining pain points. However, it would also mean delaying any potential improvements to the screen curtain functionality, leaving users to grapple with the existing complexities. This