Setting column width in Shiny app table

shiny
,
1

Hi, I'm grooming a table for publication of a searchable database. However some columns need to be significantly wider and the following code is not making any difference. Can you think why and what I could do to increase these 2 fields (Summary and Title)?

Also: fixedHeader = TRUE
and
scrollX = TRUE
are not working.
Thank you!
... # Render DataTable
output$vidTable <- renderDT({
datatable(filteredData(),
options = list(
pageLength = 10,
fixedHeader = TRUE,
scrollX = TRUE,
columnDefs = list(
list(width = '400px', targets = which(names(filteredData()) == "Summary")),
list(width = '250px', targets = which(names(filteredData()) == "Title"))

2

try with options autoWidth= TRUE

3

Didn't work, thanks though