Cannot See the Sketch Plugin of Kactus
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### Description

Hi on my MBP I cannot see the Kactus plugin in Sketch. What am I doing wrong?
### Version

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**Kactus version:** [0.3.1]

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**OS version:** [MacOs High Sierra]

### Steps to Reproduce

1. [First step]
1. [Second step]
1. [and so on]

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**Expected behavior:** [What you expected to happen]

**Actual behavior:** [What actually happened]

**Reproduces how often:** [What percentage of the time does it reproduce?]

### Logs

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#### Additional Information

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