title: Problem with running emmeans (error in assign '.Last.ref_grid')
body: <p>I have been having trouble with running emmeans function (from the emmeans package) whenever I try to follow up a two way between groups ANOVA with estimated marginal means.</p>
  <p>A simple example:</p>
  <pre><code>library(emmeans)
  library(tidyverse)
  
  df &lt;- tibble(fct1 = factor(rep(1:3, 10)),
               fct2 = factor(rep(2:1, 15)),
               DV = rnorm(30, 100, 15))
  
  
  model1 &lt;- lm(DV ~ fct1 * fct2, df)
  
  emmeans(model1, &quot;fct1&quot;, by = &quot;fct2&quot;)
  </code></pre>
  <p>Returns:</p>
  <pre><code>Error in assign(&quot;.Last.ref_grid&quot;, object, inherits = TRUE) : 
    cannot change value of locked binding for '.Last.ref_grid'
  </code></pre>
  <p>No matter what data I run it on, always the same error shows up.</p>
  <p>Thank you for any help!</p>