REPL Speed in Juno/JuliaPro vs Julia REPL

Hi. I’m a new user and I’m working through the JuliaAcademy data science tutorial (except I’m trying to run the examples in JuliaPro instead of the notebooks because I don’t like notebooks very much).

I have a question about the REPL in Juno. It seems to be very sluggish, especially compared to the REPL when I just load Julia without Juno. For example, if I type the following command:

A = rand(100,100)

It takes the Juno REPL 5 seconds to render the result.

If I then type this command:


it takes another 5 seconds for the Juno REPL to render the result.

If I just type a number in the REPL prompt:


it displays the result immediately. However, the prompt is frozen for 5 seconds before I can start typing a new command into the prompt.

All of these commands are practically instantaneous in the Julia 1.5.2 REPL (without the Juno IDE).

I’m wondering if all this is normal. I had this problem both in JuliaPro and in Juno installed on top of Atom as described here:

I searched the internet for a solution, and a suggestion I found was to enable an option called Fallback Renderer. This option appears to be unavailable in the current version of JuliaPro (1.5.2-1).

I’m running this all on Windows 10.

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