8 files declare their use of SingleAssetOptimizerBase in Advanced CSS/JS Aggregation 8.3

CssMinifier.php in advagg_css_minify/src/Asset/CssMinifier.php

JsMinifier.php in advagg_js_minify/src/Asset/JsMinifier.php

MinificationSubscriber.php in advagg_ext_minify/src/EventSubscriber/MinificationSubscriber.php

MinificationSubscriber.php in advagg_css_minify/src/EventSubscriber/MinificationSubscriber.php

MinificationSubscriber.php in advagg_js_minify/src/EventSubscriber/MinificationSubscriber.php

MinificationSubscriber.php in advagg_bundler/src/EventSubscriber/MinificationSubscriber.php

Minifier.php in advagg_ext_minify/src/Asset/Minifier.php

TranslateCss.php in advagg_mod/src/Asset/TranslateCss.php