Is PlantUML Viewer — Local UML Diagram Tool safe to install?

What data it declares

The developer declares that it does not collect or use your data.

The developer also certifies that your data is not sold to third parties outside approved uses, not used for purposes unrelated to the extension's core function, and not used to decide creditworthiness or lending.

The listing does not link to a privacy policy.

This is the developer's own declaration in the Chrome Web Store. We cannot check it against what the extension does.

What Chrome asks you to allow

When you add it, Chrome asks you to allow it to:

• Read and change all your data on all websites

Derived from the manifest by Chrome's documented rules; the dialog's exact wording depends on your Chrome version and language. Chrome asks again if an update requests more.

What it can reach

No site access is declared in the manifest, so it cannot read the pages you open on its own.

Worth knowing

• Run its own code on the pages it can access scripting

Routine for an extension

• Store data in your browser storage

Pages it runs its code on

It runs its own code on every page you open: the manifest declares a content script for all sites.

• https://gitlab.com/* only gitlab.com
• https://bitbucket.org/* only bitbucket.org
• https://codeberg.org/* only codeberg.org

A content script is code the extension injects into pages matching these patterns. On those pages it can read and change what you see, whether or not a host permission is listed above.

What it may ask for later

Not granted when you add it: Chrome asks you the moment the extension requests one of these, and you can refuse. It may later ask for access to every site.

• http://*/* every site
• https://*/* every site

How usual this is for its category

In Productivity · Developer, 30% of extensions ask for access to every site. This one: Runs its code on every site.

The typical extension there declares 3 browser permissions; this one declares 2 browser permissions.

Counted over the live extensions of the same category after our latest full pass of the store. A share is context, not a verdict: what is normal depends on what the extension is for.

Who uses it and how it is kept up

58 users

• Last updated in the store 58 days ago, on 2026-09-07.
• No new version in the last 90 days.

What the store shows

The store shows none of its badges on this listing. Most listings carry none.

Has it asked for more over time?

This is the question a permission list on its own cannot answer. An extension that shipped narrow and widened later is a different proposition from one that always asked for the same thing.

The permissions this extension requests have not changed since we started watching it.

Who publishes it

Red Digits, who publishes 18 listings we track. This listing has been in the store since 2026-09-07 and was last updated on 2026-09-07.

Similar extensions that ask for less

Listings close to this one in what they say they do, which declare less reach. Less reach is not a verdict on either: compare what each needs for the job.

1. PlantUML Anywhere No permissions at all · No permissions declared 23 users ★ 5.0
2. zGPT uml No permissions at all · No permissions declared 21 users
3. PlantUML Editor No site access · 1 permission 378 users ★ 5.0

How to check or remove it in Chrome

1. Type chrome://extensions in the address bar and find the extension in the list.
2. Open its details. The site access setting shows where it can run; set it to run only on click and it reaches a page only after you press its icon.
3. To uninstall it, choose Remove on the same page.

Questions people ask

What can PlantUML Viewer — Local UML Diagram Tool access?

No site access is declared in the manifest, so it cannot read the pages you open on its own. It declares 2 browser permissions.

What data does PlantUML Viewer — Local UML Diagram Tool collect?

The developer declares that it does not collect or use your data. This is the developer's own declaration in the Chrome Web Store. We cannot check it against what the extension does.

Has PlantUML Viewer — Local UML Diagram Tool asked for more permissions over time?

The permissions this extension requests have not changed since we started watching it.

Does PlantUML Viewer — Local UML Diagram Tool publish a privacy policy?

No, the store listing does not link to a privacy policy.