Serial Monitor swallowing leading and repeated spaces

[paulwas]

Describe the bug
Today I copied the nightly build files (arduino-ide_nightly-20211008_Windows_64bit) and launched the Arduino IDE to continue work on my current project. I'm outputting a lot of formatted data via the Serial Port to the Serial Monitor (115200 baud) and have been using this IDE (2.0 Beta) for a number of weeks. The Serial Monitor has been working fine until last nights build. Now all the leading spaces have disappeared. So for example:
This output:

Events:
  List 'E'
  Add  'EA mm/dd/yyyy rr Annual|Once Description..'
  Edit 'EE nn [mm/dd/yyyy] | [rr] | [Annual|Once] | [Description..]'
  Del  'ED nn'
Time/Date:
  Get  'T'
  Set  'T [mm/dd/yyyy][hh:mm[:ss][am/pm]]'

Now looks like this:

Events:
List 'E'
Add  'EA mm/dd/yyyy rr Annual|Once Description..'
Edit 'EE nn [mm/dd/yyyy] | [rr] | [Annual|Once] | [Description..]'
Del  'ED nn'
Time/Date:
Get  'T'
Set  'T [mm/dd/yyyy][hh:mm[:ss][am/pm]]'

To Reproduce
Steps to reproduce the behavior:

1. Serial.print(" xyz");
2. Output looks like this "xyz"

Expected behavior
The serial output should now swallow any characters that are output.
Output should look like this " xyz"

Desktop (please complete the following information):

• OS:
  Edition Windows 10 Pro
  Version 21H1
  Installed on ‎1/‎16/‎2021
  OS build 19043.1237
  Serial number 011754392857
  Experience Windows Feature Experience Pack 120.2212.3530.0
• Version: arduino-ide_nightly-20211008_Windows_64bit

[paulwas]

Just realized it's also converting multiple spaces to a single space.
So all formatted output is impossible.

[paulwas]

This was enough of a deal-breaker that I went back to Beta 11 until it gets fixed.

[tomjennings]

Same here. 1.8.19, vs 2.0, all multiple spaces suppressed.

Here's a snapshot of a "datascope" in 1.8.19:

And the same sketch running in 2.0:

Also jamming serial monitor into the tiny compiler-output area is a related fail as well, but a separate issue.

[UKHeliBob]

Tab commands in print statements are also apparently ignored or at least reduced to a single space by this problem which gives the same effect

[per1234]

Tab commands

There is a dedicated issue about the problem with tabs: #675

(though I think it is likely these two issues are only different symptoms of the same bug)