NextChapter extension - The "IndexedDB / Local Storage" Question

HassanElFattmi 0 Reputation points
2026-08-09T16:02:25.5033333+00:00

Hi team,

We are currently preparing Microsoft Edge support for NextChapter, an open, local-first browser extension designed for seamless manga and webtoon reading tracking.

Because we prioritize total user privacy and instant offline sidebar access, NextChapter operates with zero cloud telemetry or external databases. Instead, our client-side engine automatically captures reading history across multiple sites, builds an offline library with cached thumbnail blobs, and powers a rich React sidebar dashboard, storing everything locally in IndexedDB via Dexie.js.

As our users' libraries grow to thousands of chapters and high-res covers, the local database becomes quite substantial. In standard Chrome, we know IndexedDB data can occasionally be evicted if the user's OS hits severe disk pressure unless navigator.storage.persist() is granted.

Before we launch on the Edge Add-ons store, I want to clarify a few technical behaviors:

  1. Does Microsoft Edge follow the exact same storage quota and temporary vs. persistent eviction logic as Chromium?
  2. How does Edge handle navigator.storage.persist() requests for Manifest V3 sidebar extensions? Does Edge auto-grant persistence based on user interaction metrics differently than Chrome?

We want to ensure our users never lose their local reading progress or custom library caches when switching to Edge. Thanks for any insights!

Microsoft Edge | Browser extensions | Windows 11
0 comments

1 answer

Sort by: Most helpful
Most helpful Newest Oldest
  1. Carl-L 20,565 Reputation points Microsoft External Staff Moderator
    2026-08-11T06:27:34.7+00:00

    Hello HassanElFattmi,

    Welcome to Microsoft Q&A forum.

    Regarding the storage quota of Edge, IndexedDB, Cache API, or Origin Private File System Access API can take up to 60% of the device total disk capacity. And they can all be candidate for eviction unless marked as persistent, this even if not totally match, closely mirrors Chromium core behaviors, since Edge is also a Chromium based browser. For more information, you can check on this article.

    I cannot find any clear statements from Microsoft regarding the eviction logic. However, as I checked, persistent storage behavior is largely handled by Chromium itself. As I don't see any Edge divergent behavior, the safest suggestion here is do not rely on auto approval and check regularly important data for manual handling if needed.

    If the answer is helpful, please click "Yes". If you have extra questions about this answer, please click "Comment".

    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

    Was this answer helpful?

    1 person found this answer helpful.

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.