DatePickerSingle -- very slow performance when many disabled_days?

[dsargent]

I have a DatePickerSingle with a range from Feb 1 2020 to "today". We have a daily job that runs and sometimes we save the output -- I want to disable days where we didn't save output so the user cannot choose those days. We have about 297 days in that range that need to be disabled.

When opening the date picker, it is very slow to appear (5-10 seconds) and then clicking through the months is ultra slow and laggy. If I remove the disabled_days property or set it to just one date, the control behaves fine.

Is this an unreasonable use case?

Here's a recording. You can't see me actually clicking, but here I was clicking to scroll the months as fast as it would allow, so all the lag is due to waiting for the control to update.

Also I noticed the days of the week (Su Mo etc.) are misaligned with the numbers for the dates -- but I don't think this is related to the disabled_days issue.