Introduction
A link preview will appear automatically when you add a URL Google Docs, Slides, or Drawings. We have seen how this can become a problem for a school. The issue usually comes up when a teacher notices a student watching a video mid-assignment in the video preview by adding a YouTube link to a Doc or Slide. This causes distractions and access to restricted content.
In our work with Safe Doc, we have found that schools need centralized control for student accounts, while Google’s Show link details only works for individual users. So schools need a way to disable link preview in Google Workspace for all students.
Schools network and web filters control website access, but not link previews inside Google Workspace. This post explains why website blocking does not stop previews, why Google’s setting is limited, and how Safe Doc’s BlockDocLinkPreview policy solves it.
Why Link Previews Can Be a Problem for K–12 Schools
Google Workspace link preview with thumbnail, title, and description
The problem starts when a student adds links to Google Docs, Slides, or Drawings and a preview appears. Instead of using the link, students can see extra content while working on their assignments. This can create a few separate problems.
Distraction During Classwork
One issue we see is students focusing on the content shown in the link preview instead of the assignment they are working on. They can see an image, video, or snippet attached to the link instead of simply working with the link. This extra content can distract them from the assignment or the work they are doing.
Access to Content
Another one is access to content that the school has already restricted. For example, a student can paste a YouTube link into Google Docs or Slides and see the video through the preview even when direct access to YouTube is blocked.
Schools can use web or content filters to restrict websites such as YouTube. However, those restrictions do not disable link preview in Google Workspace. The website is restricted, but the content from the URL can still be displayed through the Workspace preview.
The Problem for School IT Administrators
We have seen school IT teams looking for centralized ways to manage Google Workspace features across student accounts, when individual user settings are not enough. The goal is not to turn off a preview for one student. But it is to disable link previews for all the student accounts while keeping the underlying links available.
If these link previews are left unaddressed, teachers have to deal with the distraction, while IT administrators have to address cases where students use previews to get around existing web or YouTube restrictions.
Website Blocking vs. Blocking Link Previews
How Website Blocking Works
Blocking a website and blocking a link preview are two different controls, A School’s web content filter or chrome URL blocking controls access to a destination. For example, a school can block direct access to YouTube for student accounts.
When a student tries to open a restricted website directly, the restriction is applied to that website. These controls are designed to manage access to the website itself. They do not provide a separate control for how a URL is displayed inside another Google Workspace application.
How Link Previews Work in Google Workspace
The important difference is that the preview is displayed inside the Workspace application. The student does not necessarily have to open the website directly to see the preview content. This means a website filter can restrict access to the domain while the Workspace apps can still display the information related to the URL.
This becomes more important when few websites are restricted. For example, a student can add a YouTube URL to Google Docs or Slides and still see the video through the link preview, even when direct access to YouTube is blocked by the school’s content filter. The preview is being displayed inside the Google Workspace editor, so blocking the website does not block the preview itself.
What Google Docs Provides for Link Preview Control
Among all the google workspace apps like Google Docs, Slides, and Classroom, Google does not provide a centralized setting to turn off link previews. However Google Docs includes a built-in Show link details setting.
Google Docs > Tools > Preferences > Show link details
Google Docs Show link details setting in Tools and preferences
Users can turn this option off to stop link details and previews from appearing in their own Docs. However, this is a personal user setting, not an admin control.
Each user has to change it in their own account, so an administrator cannot use it to disable link previews for all student accounts or a specific Organizational Unit. The setting also does not automatically apply to other users or shared documents. For an individual user, this setting is easy to manage.
But For K–12 schools, the main problem is that administrators cannot turn off link previews for students from one central setting. They need a way to apply the setting to the student accounts or Organizational Units they manage. Like for a school with student accounts, they need a way to manage the feature centrally, especially across a large number of accounts.
What an ideal solution should provide for a school, the solution should:
- It should give admins centralized control like they should be able to set the policy at the Organizational Unit(OU) level instead of individual settings.
- The solution should cover the main Google Workspace apps, that is Docs, Slides,Classroom and Drawings.
- It should Block the preview and access itself like previews from appearing, including preview cards and access to videos or content.
- Admins should be able to check and manage the policy easily.
- Work through Google Admin Console and Chrome management, alongside the school’s existing policies.
How Safe Doc BlockDocLinkPreview Policy Solves This
For schools using Google Workspace, Safe Doc provides a feature-level policy for controlling link previews through the Chrome browser.
Safe Doc BlockDocLinkPreview policy blocks the automatic link preview from appearing when users add or paste links. The policy blocks link previews Across the Google Workspace apps like Google Docs, Slides, and Drawings.
Google does not provide an administrator-managed setting for centrally controlling this particular link-preview feature. Safe Doc adds this administrative control through its managed Chrome extension, allowing administrators to apply the restriction to specific users or Organizational Units (OUs).
The policy can be configured through the Google Admin Console and applied to the student Organizational Units(OU) that needs the restriction.
This is different from blocking the website itself. The goal is to control the preview feature inside Google Workspace, rather than block the URL or website through any web filter. This lets the school stop the preview cards or thumbnails from appearing.
The policy also solves the main limitation of the Google Docs Show link details setting. Instead of an individual setting, the administrator can configure the Safe Doc policy once and apply it to the required student accounts or Organizational Units.
This gives administrators a targeted way to stop the preview, without blocking the underlying links they still need to use.
“The control needs to affect functionality inside the Google Workspace editor itself. There was no API for managing this setting, and Chrome extensions such as Safe Doc could interfere with built-in features. Therefore, the enforcement point is the managed Chrome environment where the Google Workspace editor is running.”— Neeraj Nanvani, Development Director of Safe Doc at xFanatical
Link Previews in Google Docs
When a link is added to a Google Doc, a preview can appear automatically. To disable link preview for students, Safe Doc’s BlockDocLinkPreview policy blocks the preview while keeping the link usable.
Disable Link Preview Feature in Google Docs
Link Previews in Google Slides
When a link is added to a presentation, Google Slides can show a preview. They can distract students from the presentation or lesson. Safe Doc’s BlockDocLinkPreview policy blocks these previews.
Restrict Link Preview Feature in Google slides
Block YouTube Previews in Google Slides
YouTube links can show video previews in Google Slides. Students can see the video through the preview. Safe Doc’s BlockDocLinkPreview policy blocks the preview in the google slides.
Restrict Youtube Link Preview Feature in Google Slides
Block Link Preview Feature in Google Drawings
Students can add links to their Drawings projects, and It shows a preview of the linked content. Safe Doc’s BlockDocLinkPreview policy blocks the preview while keeping the link usable.
Block Link Preview Feature in Google Drawings
Remove Link Preview Feature in Google Classroom
Google automatically generates a preview with a thumbnail and additional content when a link is added. This can distract students, the policy lets administrators disable the preview so only the link remains.
Remove Link Preview Feature in Google Classroom
How to Disable Link Previews in Google Docs, Slides, and Drawings With Safe Doc
If you have not deployed Safe Doc yet, apply for a free 30-day trial license key. The trial license and sample policy JSON file will be sent to you by email.
Next, sign in to the Google Admin Console and deploy xFanatical Safe Doc to the student organizational unit (OU) where you want to apply the restriction. You can refer to the guide, How to Deploy Safe Doc To Your Students’ Chrome Browsers, and use your trial license along with the sample JSON file to activate the extension.
Steps for Configuring Safe Doc Policy settings:
- Sign in to the Google Admin Console.
- Go to Devices > Chrome > Apps & Extensions > Users & browsers, navigate to your Safe Doc policy configuration for the relevant organizational unit (OU).
- Click the xFanatical Safe Doc app.
- In the right-hand panel, under Policy for extensions, add or edit the policy configuration JSON to include BlockDocLinkPreview:
{
"BlockDocLinkPreview": {
"Value": true
}
}
Setting "Value": true blocks link previews. - Click Save to apply the changes.
- Verify that link previews are blocked in Google Docs, Slides, and Drawings. The link should remain usable, but the preview or thumbnail should not appear.
Safe Doc blocks the preview, while the underlying URL remains usable. If your school uses any filtering tool, Safe Doc works alongside it to close the specific link-preview.
Video
What Changes After You Enable BlockDocLinkPreview ?
The goal here is not to make links not usable in Google Workspace. It is to stop the automatic preview card that appears when a link is added, while keeping the link itself usable.
Once the policy is enabled, students no longer see the automatic preview or thumbnail when a link is added to Docs, Slides, Drawings, and Classroom. This also prevents YouTube previews from appearing inside these apps. The link itself still works, so students and teachers can add and use links normally. Only the preview is blocked.
Instead of blocking it completely or adding more network filtering, Control the specific feature causing the problem.
Frequently Asked Questions
- Can administrators centrally disable link previews?
Yes, with Safe Doc's BlockDocLinkPreview policy, administrators can disable link previews at the Organizational Unit level through the Google Admin Console, Safe Doc is deployed as a managed Chrome extension, so administrators can apply the policy to selected users without relying on individual settings. - Can I disable link previews without blocking the links?
Yes. Safe Doc blocks the link preview, not the underlying URL. You can still add and use the link, but the preview card or thumbnail will not appear. - Does BlockDocLinkPreview work in Google Slides, Docs, Drawings, and Classroom?
The BlockDocLinkPreview policy works across Google Workspace surfaces including Docs, Slides, Drawings, and Classroom. Administrators can apply the policy to the users or Organizational Units they manage instead of configuring each app or account separately. - Is “Show link details” a school-wide Google Admin setting?
No. Show link details is a user-level setting in Google Docs Only. It has to be changed individually by each account and it does not give any way for IT administrators to enforce it across a school or Organizational Unit(OU). - How does Safe Doc apply this policy after it is enabled in Google Admin Console?
Safe Doc is deployed as a managed Chrome extension to the selected student Organizational Unit. Once BlockDocLinkPreview is configured in the Safe Doc policy settings, the restriction applies to users in that OU without requiring students or teachers to change their own settings.
Conclusion
Link previews in Google Docs, Slides, and Drawings can create problems for K-12 schools. They can distract students from their work, and they can let students reach YouTube content or any other content through previews even when the school has already blocked YouTube.
Google does not provide a centralized setting to turn off link previews. The built-in Show link details in google docs option is an individual control over the feature, but it does not provide the centralized control a school IT administrator needs.
Safe Doc’s BlockDocLinkPreview policy gives admins a way to manage this centrally across supported Workspace apps and disable link previews in Google Workspace. Start a free trial, if you have not yet deployed Safe Doc.
xFanatical Safe Doc
