Migrating

Migrating from another plugin

MM Optimizer detects other image optimizers and stands down rather than fighting them.

What happens while another plugin is active

Still running	Switched off
Conversion of new uploads	<picture> delivery
Bulk conversion	.htaccess rules
Diagnostics and recommendations
Migration tools

Conversion keeps running on purpose: the derivatives get built while the other plugin is still serving, so switching over is instant rather than a wait.

An admin notice names the plugin it found. Detected: EWWW Image Optimizer, Converter for Media, Imagify, ShortPixel, Smush and Optimole — including renamed folders, and deactivated plugins that left rewrite rules behind in .htaccess.

Coming from Converter for Media

The Bulk conversion tab gains an import section.

Import the settings reads the other plugin's configuration and maps it onto the nearest optimization level. It maps to a level rather than copying the raw quality number, because the levels are calibrated against real measurements and a single inherited number is not.

Adopt the converted files takes the WebP and AVIF files already in wp-content/uploads-webpc/ and moves them into place, turning a multi-hour re-encode into a directory scan.

Adopt or regenerate?

Adopt if you want to switch over now. It takes minutes.

Regenerate if you can spare the time, and especially if the inventory is mostly WebP. Converter for Media installations in the wild rarely have much AVIF, and AVIF is where the remaining gain is — roughly 20% beyond WebP on photographic content. The screen tells you when this applies to your library.

You can adopt first and regenerate later; adopted files are replaced as the bulk run reaches them.

Switching over

1. Install and activate MM Optimizer alongside the existing plugin.
2. Open Diagnostics and apply the recommended configuration.
3. Run Bulk conversion to completion. Delivery is still off at this point.
4. Deactivate the other plugin.
5. Remove its rewrite rules if it left any — check .htaccess in your site root, wp-content/ and wp-content/uploads/ for its marker block.
6. Reload the MM Optimizer settings. Delivery arms itself automatically. If the red Image delivery is off notice is still there, the Delivery tab is set to No delivery (1.0.0 saved that when applying its recommendation during a conflict): choose <picture> and save.
7. Load a page and confirm images are being served as AVIF or WebP in your browser's network panel.

Nothing is deleted from the other plugin. If you want to go back, reactivate it.

Coming from EWWW

EWWW writes its WebP files next to the originals, using the same naming scheme this plugin uses. Existing files are picked up as they are, so there is no adoption step.

One extra note: while EWWW is active, in-place thumbnail optimization stays off here too. Both plugins would be rewriting the same files, which is a genuine risk of corruption rather than a theoretical one.