Template Override Manager - Quick Start

Installation

1. Download com_overrides_1.0.0.zip
2. In Joomla admin, go to System → Install → Extensions
3. Upload and install the ZIP file
4. Access via Components → Template Override Manager

Quick Workflow

First Time Setup

1. Select your template from the dropdown
2. Click "Generate newhtml" (creates baseline from current extension files)
3. Click "Create Checkpoint" (saves baseline as oldhtml)

After Extension Updates

1. Click "Generate newhtml" (refreshes baseline with updated extension files)
2. Run three-way diff:

   meld templates/[template]/html overrides/[template]/newhtml overrides/[template]/oldhtml

3. Review what changed in the extension (newhtml vs oldhtml)
4. Update your template overrides as needed
5. Click "Create Checkpoint" (saves current state for next comparison)

What It Does

• Scans your template's /templates/[name]/html directory for overrides
• Finds the source files in components and modules
• Copies them to /overrides/[template]/newhtml
• Allows checkpointing to /overrides/[template]/oldhtml
• This enables three-way diff to see what changed in extensions

Interface Elements

Discovered Overrides: Lists all components and modules you've overridden, showing:

• Green badge = Source file found
• Yellow badge = Source file missing (extension might be uninstalled)
• Full paths to source files

Actions:

• Generate newhtml: Copy current extension source files to baseline
• Create Checkpoint: Save current baseline as old baseline
• Clear: Remove newhtml or oldhtml directory

Why Three Baselines?

1. Your overrides (/templates/[name]/html): Your customized files
2. New baseline (/overrides/[name]/newhtml): Current extension files
3. Old baseline (/overrides/[name]/oldhtml): Extension files from last checkpoint

Comparing all three shows:

• What you changed (your overrides vs old baseline)
• What the extension author changed (new baseline vs old baseline)
• What you need to update (merge extension changes into your overrides)

Meld Example

cd /path/to/joomla
meld templates/mytemplate/html overrides/mytemplate/newhtml overrides/mytemplate/oldhtml

In Meld's three panes:

• Left: Your custom overrides
• Middle: Current extension files (after update)
• Right: Original extension files (before update)

Changes between middle and right = what the extension author changed → Helps you decide what to update in your left pane

Notes

• Only manages site template overrides (not admin)
• Component is admin-only (no impact on live site)
• Requires write permissions on Joomla root
• Works with both Joomla 3 (legacy) and Joomla 4+ (modern) file structures

Support

Full documentation in README.md