Credit to srikat 👑 for plugin oxygenthemeenabler
Credit to Elliot Condon for ACF 💭
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Problem: you want to progressively move pages over to Oxygen yet there’s no easy way to switch rendering between Oxygen and your theme and its third-party builders.
Solution: a nice setup that allows you to easily toggle Oxygen rendering on/off on a per page basis using existing plugins and a few new lines of code.
Background: Oxygen is the name of a premium software addon for the WordPress content management system for websites. By default Oxygen completely disables WordPress’s themes.
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Steps
Step 1
Oxygen should be installed.
Step 2
Install the modded Oxygen theme enabler plugin (ZIP direct download) and activate it.
Step 3
Switch the theme enabler to default to theme. Do this under Oxygen > Theme Enabler > Use theme for most pages.
Step 4
Install the mighty ACF plugin (from WordPress.org) and activate it.
Step 5
Import this ACF prebuilt setup (.JSON direct download) under Custom Fields > Tools > Import.
Step 6
Celebrate? This is how your Edit Page screens should then look – with the Classic Editor (WordPress.org plugin page).
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Technical Notes
How-it-works:
• Use Sridhar’s plugin* to force rendering to the theme.
• Use ACF to create checkboxes for pages.
• *Modify the plugin to check for pages’ ACF meta value and switch to Oxygen accordingly.
Tested working with:
Oxygen 3.5 RC 1,
Theme Enabler 1.0.2 modded,
Advanced Custom Fields 5.8.14,
WordPress 5.4.2,
PHP 7.4.9.