Best Imagus alternatives in 2026
Imagus has carried sieve-rule hover zoom for over a decade, but development pace varies and Manifest V3 has been a struggle for the entire family of legacy hover-zoom extensions. If you’re looking for an Imagus alternative, here’s an honest ranking by privacy, maintenance, MV3 readiness, and how well your sieve workflow carries over.
The shortlist
- Ultra Zoom — actively maintained, MV3-native on Chrome and a current Firefox add-on, zero telemetry, on-device AI upscaling. Supports custom URL rules in Pro for migrating sieves. ultrazoom.app
- Hover Zoom Plus — the most-installed Hover Zoom fork. No sieve, but covers most popular hosts. Full comparison.
- Mage and other Hover Zoom forks — sporadic releases, single maintainer, partial MV3. Full comparison.
- Thumbnail Zoom Plus (Firefox) — a classic that broke when legacy add-ons retired. Full comparison.
What happens to your Imagus sieve
- Most popular hosts: covered by Ultra Zoom’s built-in plugins out of the box — no rules needed.
- Long-tail hosts: generic hover-zoom shows the largest image the page provides, without you writing anything. Where a sieve reached a bigger original than the page serves, you need a custom rule.
- Your custom rules: Ultra Zoom Pro supports custom URL rules. Most Imagus rules translate directly — the regex / capture-group pattern is the same shape.
- Heavy sieve users: if you maintain hundreds of personal rules, expect to spend an hour porting the ones that matter. Plugins replace most rules over time.
Side-by-side comparison
| Feature | Ultra Zoom | Imagus | Hover Zoom Plus |
|---|---|---|---|
| Sieve-style URL rules | ✓ (Pro) | ✓ | – |
| Auto-updating community rule pack | – | Manual sieve | – |
| Site-specific plugins | ✓ | Limited | ✓ |
| Theater mode | ✓ | ✓ | – |
| Reverse image search shortcuts | ✓ | ✓ | – |
| On-device AI upscaling | ✓ (Pro) | – | – |
| Video preview controls | Preview free on Reddit & Imgur; controls (Pro) | – | – |
| Active development | Every few weeks | Variable | Limited |
| Manifest V3 native | ✓ | Partial | Partial |
| Zero telemetry guarantee | ✓ | Unclear | Unclear |
Try it free
The core extension is free forever, with 34 built-in site plugins. Pro adds 18 more plugins and custom URL rules, with a 7-day free trial when you’re ready. See plans.