`kableExtra::kable()` rendering of tables looks weird

[ValeriVoev]

I have this simple document:

---
title: "TEST"
author: TEST
output:
  rmdshower::shower_presentation:
    self_contained: false
    katex: true
    ratio: 16x10
---

Slide with R Code and Output

library(dplyr)
head(iris) %>% kableExtra::kable()

but the output of the table looks really weird - for example lines between the rows extend to the whole width of the slide and some of the columns are "glued" to each other (there is no space between them). Is there some incompatibility between shower and kable?

[rocksms]

Have similar problems and looking for answers too!