Removing the full width of a kableExtra table using a popover - r-markdown

Question

Continuing with the answer to a previous SO question here, the resulting table is occupying the entire width of a slidy_presentation despite the command kable_styling(full_width=F) being utilized. As I am still new to the kableExtra package and RMarkdown as a whole, I have a feeling it might be due to the long footnote at the bottom of the table.
As a result, I am trying to utilize the HTML "popover" feature as suggested in the R vignette Awesome Table in HTML. In particular, I am trying to create a "Note" field in the last row of the x column from the following .RMD file.
RMD file:
---
title: "Untitled"
output: slidy_presentation
---
```{r}
library(kableExtra)
library(dplyr)
```
Include the HTML script from vignette here.
```{r echo=FALSE}
prob.success <- sample( seq(.5,.99,.01), size=1 )
conf.alpha <- sample( seq(.5,.99,.01), size=1 )
tab1 <- data.frame( x=0:5, f=round(dbinom(0:5,5,prob.success),3) ) %>%
mutate( pe=x/5, lcl=qbeta(1-conf.alpha,x+0.5,5-0:5+0.5) ) %>%
mutate( lcl=pmin(pe,lcl) ) %>%
mutate( delta=pe-lcl ) %>%
mutate( f_delta=f*delta )
exp.expr <- "$\\sum_x f(x)*\\left ( pe(x) - lcl(x) \\right )$"
exp.delta <- format( round(sum( tab1$f_delta ),4), nsmall=4 )
tab2 <- tab1 %>%
mutate( x=as.character(x), f=format(round(f,4),nsmall=4) ) %>%
mutate( pe=format(round(pe,4),nsmall=4) ) %>%
mutate( lcl=format(round(lcl,4),nsmall=4) ) %>%
mutate( delta=format(round(delta,4),nsmall=3) ) %>%
mutate( f_delta=format(round(f_delta,4),nsmall=4) ) %>%
rbind( ., data.frame(x="", f="", pe="Exp", lcl="Diff", delta="=", f_delta=exp.expr) ) %>%
rbind( ., data.frame(x="",f="",pe="",lcl="",delta="=",f_delta=exp.delta) )
tab.cols <- c( "x", "f(x)", "pe(x)", "lcl(x)", "pe(x)-lcl(x)",
"$f(x)\\times\\left(pe(x)-lcl(x)\\right)$" )
kable( tab2, format="html", escape=FALSE, align="c", col.names=tab.cols ) %>%
kable_styling( "striped", full_width = F, position="center" ) %>%
footnote( general="Given x successes out of n trials, the holistic Jeffreys $100*(1-\\alpha)\\%$ Lower *Credible* Limit is the value $p$ such that $\\int_0^p \\frac{t^{x+0.5-1}(1-t)^{n-x+0.5-1}}{B(x+0.5,n-x+0.5)} dt = \\alpha$ where B(a,b) is the Beta function given by $\\int_0^1 t^{(x-1)}(1-t)^{(y-1)} dt$.",
general_title="Note:", footnote_as_chunk=TRUE, escape=FALSE )
My attempt thus far
With the only change to the R chunk above being with the variable tab2, here is what I have tried.
tab2 <- tab1 %>%
mutate( x=as.character(x), f=format(round(f,4),nsmall=4) ) %>%
mutate( pe=format(round(pe,4),nsmall=4) ) %>%
mutate( lcl=format(round(lcl,4),nsmall=4) ) %>%
mutate( delta=format(round(delta,4),nsmall=3) ) %>%
mutate( f_delta=format(round(f_delta,4),nsmall=4) ) %>%
rbind( ., data.frame(x="", f="", pe="Exp", lcl="Diff", delta="=", f_delta=exp.expr) ) %>%
# Change is only with the last line
rbind( ., data.frame(x=cell_spec("Note",popover=spec_popover(content="Test",title=NULL,position="bottom")),
f="",pe="",lcl="",delta="=",f_delta=exp.delta) )
and the popover feature doesn't work.