Critical Error from using Nothing(item)

[Grimmer von Grim]

Critical Error

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A critical error has occurred. Please create a bug report on the forums here. Please include what you did before the error and a screen-shot or copy-paste of the error message below:

 Version: 0.69.420-PUBLIC#1719 Message: useFunction for (EmptySlot) must be overriden in a child class! Stack:
TiTSException: useFunction for (EmptySlot) must be overriden in a child class!
    at r (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:9571055)
    at o.value (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:5675813)
    at o.value (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:5012892)
    at o.value (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:11978517)
    at Object.doClick (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:11981502)
    at https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:11898470
    at s (https://www.fenoxo.com/play/TiTS/release/main.a7c38a8d.js:1:10194595)

Here's the error message