Nightspar — Vocabulary Flashcards, Any Page Firefox

Nightspar — Vocabulary Flashcards, Any Page

Save words from any page. AI builds a complete flashcard for the meaning used in that sentence; spaced repetition makes it stick.

Features & Capabilities

Stop forgetting the words you look up.

Select a word or phrase on any page and save it. Nightspar writes the whole flashcard for you — the meaning as it's used in that sentence, a translation, pronunciation, example sentences, and audio — then schedules it for review right before you'd forget.

WHAT IT DOES

• Save from anywhere — select text on any page and click the "+" button. No copy-paste, no tab switching, no interruption to your reading. • Cards that write themselves — every meaning, with its own translation and example. The definition describes the sense actually used in your sentence, not just the most common one. • Hear it — natural-sounding audio for every phrase. • Organize as you go — drop a phrase into a collection right from the save panel. • Spaced repetition that works — reviews are scheduled with FSRS, the same modern algorithm Anki uses. A few minutes a day. • 34 languages, several at once — each language pair keeps its own library and review schedule. • Your library, on the web too — everything you save syncs to nightspar.com.

WHAT IT SAVES, AND WHEN

When you save a phrase, Nightspar also stores a short snippet of the text surrounding it, plus the page URL and site name. This is what lets the AI pick the right sense of a word, and lets you see where you first met it. URLs are sanitized before storage: credential-like query parameters are removed and fragments are dropped.

This happens ONLY when you explicitly save a phrase. The extension does not read, monitor, or transmit the pages you visit in the background, and it does not track your browsing. You can turn context capture off in the extension's settings at any time — with it off, only the text you selected is sent.

Requires a free Nightspar account. Free during the beta.

Privacy policy: https://nightspar.com/privacy

User Growth & Download Statistics

Manifest V3 Add-on
By:
Nightspar
Daily users:
-
Version:
1.2.1 Last updated: 2026-08-12
Version code:
6403245
Creation date:
2026-08-09
Firefox add-on GUID:
extension@nightspar.com
Firefox add-on numeric ID:
3051382
Firefox on Android:
Yes
Risk:
Moderate risk impact High risk likelihood
Permissions:
Host permissions:
  • https://api.nightspar.com/*
  • https://auth.nightspar.com/*
Content scripts matches:
  • <all_urls>
Size:
1.03MB
Email:
su*****@nightspar.com
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-09-03
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
Nightspar
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/nightspar/
Email:
su*****@nightspar.com
Website:
https://nightspar.com

Is Nightspar — Vocabulary Flashcards, Any Page Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Nightspar — Vocabulary Flashcards, Any Page requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details
  • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
  • Low ******* ****** ** *** ********* ******** *************
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Nightspar — Vocabulary Flashcards, Any Page is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • High **** ********* *** ******** ****** *** ********** *** *** ** ****** ** *****
  • High **** ********* *** *** **** ****** ********* ********** *** *** ** ****** ** *****
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