Fix SVG in LiipImagineBundle (use together with https://gist.github.com/teohhanhui/90bbc4a61888ad2e92a160d8459db300 to fix MIME type in Symfony)

FilterManager.php

<?php

declare(strict_types=1);

namespace AppBundle\Imagine\Filter;

use Liip\ImagineBundle\Binary\BinaryInterface;
use Liip\ImagineBundle\Imagine\Filter\FilterManager as BaseFilterManager;
use Liip\ImagineBundle\Model\Binary;

class FilterManager extends BaseFilterManager
{
    /**
     * {@inheritdoc}
     */
    public function apply(BinaryInterface $binary, array $config): Binary
    {
        if ('svg' === $binary->getFormat() && !isset($config['format'])) {
            $config['format'] = 'png';
        }

        return parent::apply($binary, $config);
    }
}

services.yml

parameters:
    # ...

services:
    # ...

    AppBundle\Imagine\Cache\Resolver\WebPathResolver:
        decorates: liip_imagine.cache.resolver.default
        parent: liip_imagine.cache.resolver.default
        autowire: true
        autoconfigure: false
        public: true

    AppBundle\Imagine\Filter\FilterManager:
        decorates: liip_imagine.filter.manager
        parent: liip_imagine.filter.manager
        autowire: true
        autoconfigure: false
        public: true

WebPathResolver.php

<?php

declare(strict_types=1);

namespace AppBundle\Imagine\Cache\Resolver;

use Liip\ImagineBundle\Imagine\Cache\Resolver\WebPathResolver as BaseWebPathResolver;

class WebPathResolver extends BaseWebPathResolver
{
    /**
     * {@inheritdoc}
     */
    protected function getFileUrl($path, $filter): string
    {
        $path = preg_replace('/\.svg$/', '.png', $path);

        return parent::getFileUrl($path, $filter);
    }
}