PHP Notice: undefined index in autoptimizeImages.php

Hi,

Thanks for a great plugin. We use it almost on all of our sites.

We notice that there’s a PHP Notice repeated in our error log:

PHP Notice: Undefined index: autoptimize_imgopt_number_field_7 in /path-to/plugins/autoptimize/classes/autoptimizeImages.php on line 773

Please fix it.

Thanks,
Anh

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