Pre-smush original images remain

Hi,

I find the following big problem:

I installed the Updraft Backup and migration plugin and tried it for aprox. 4 weeks. Then I deleted it, because it caused some issues with my hosting server (very high usage pics).

The problem is that all the “updraft pre-smush original images” still remain in the WP-Content, so I have an unuseful double of every image. I have thousands of images, so now I have thousands of redundant double images that I do not need at all.

I’d like to know how can I delete these double images.

Thank you.

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