First of all, thank you so much for this excellent extension!

I think I might have discovered a regression when using the flextable package with vscode-R v 2.2.0.

Describe the bug
I use the flextable package for outputting tables in rmd documents.
With previous versions of vscode-R when printing the flextable object the viewer would show the table.
However, with version v. 2.2.0 the viewer just shows a blank canvas.
When rolling back to 2.1.0 it works as expected.
I have tried printing a table with the gtsummary package and it still works with 2.2.0.

To Reproduce

flextable shows up blank in viewer:
flextable::flextable(as.data.frame(letters))

gtsummary table still works:
gtsummary::tbl_summary(as.data.frame(letters[1:5]))

but when converting to flextable it shows up blank again:
gtsummary::as_flex_table(gtsummary::tbl_summary(as.data.frame(letters[1:5])))

Do you want to fix by self? (We hope your help!)

Want to? Yes. Able to? Sadly no.

Expected behavior
Flextable tables showing in viewer as in previous versions.

Screenshots

Environment (please complete the following information):

• OS: pop_os 21.04
• VSCode Version: 1.60.0
• R Version: 4.1.1
• vscode-R version: 2.2.2