I figured how to do it, for those interested, here is how:
1°) Create a copy of the layout type you are using. For example, if you are using tabbed-no-effect, make a copy of this folder:
Copy content of:
/Joomla/modules/mod_minifrontpage/themes/tabbed-no-effect/
To new folder:
/Joomla/modules/mod_minifrontpage/themes/intro-img/
2°)
Open
/intro-img/tmpl/
bottom.php
FindAdd after// Intro image - start
$images = json_decode($item->images);
if (isset($images->image_intro) and !empty($images->image_intro)) {
echo '<div class="mfp-image-intro"><a href="';
echo JRoute::_(ContentHelperRoute::getArticleRoute($item->slug, $item->catid));
echo '"><img src="';
echo htmlspecialchars($images->image_intro);
echo '" alt="';
echo htmlspecialchars($images->image_intro_alt);
echo '"/></a></div>';
}
// Intro image - end
3°)
Repeat operation 2°) for:
/intro-img/tmpl/
lastcell.php
/intro-img/tmpl/
lastcolumn.php
4°)
Open
/intro-img/assets/css/
style.css
Add at the end.mfp-img-intro { /* This will make the intro image float on the left */
float: left;
width: 123px; /* Change the width to whatever you want */
padding: 0 10px 10px 0;
}
However, don't use an intro image if there's already an image within the article, otherwise you'll get both. We would need something to override the thumbnail in case there's an intro image. But my knowledge of php is fairly limited. That is also why the code is not optimised.
DS contant is something that has been removed in Joomla 3.0 but we still need this for some fix path purpose until we found a better replacement. Does Minifrontpage still working properly when you remove it?