Change pictures ball /ball-over / joker activ/ Joker-inakativ after a update

Question 1

If you want to overwrite the joker images, it is better to change the CSS instead of uploading and overwriting the image on the server. That will save you from having to overwrite the image after every update.

There is an “Additional CSS” field under Appearance > Customize in the WP admin where you can put this CSS*:

/* Change the multiplier image */
.fp-nojoker {
    background-image: url(https://www.bahnsport-info.de/wp-content/uploads/2021/04/joker-inactive.png)!important;
}
.fp-joker {
    background-image: url(https://www.bahnsport-info.de/wp-content/uploads/2021/04/joker-active.png)!important;
}

*) Change the URL’s to the correct ones if needed. I just picked these 2 from your website.

If you don’t want to work with images on your server, you can even create a code from it and use that in the CSS, like so*:

url('data:image/png;base64,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')

*) I used https://www.base64-image.de/ to convert the image and create the CSS url.

Question 2

After an upgrade there is a chance that some of the translations have changed or new strings were added. So it is always a good idea to update your custom .po file from the .pot file that is included in the plugin. You can do so by opening your custom translation in Poedit and then from the menu choose Translation > Update from POT file. But it is not mandatory to do so. If nothing (important) has changed and you don’t update from the POT-file, then everything should remain working.

To use your own custom translation, you should use an extension plugin that loads your translation file. And then you should be able to re-use your translation again and again without having to upload it again (unless you’ve made changes to it).