Options Menu - Load/Save - .pln

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Yes and done.
Are you using Developer Mode or made changes in it?
Brief description of the issue:
Opening ‘Load/Save’ menu only gives the ‘.FLT’ option - no ‘.PLN’ option.
In order to have .pln files visible, enter ’ .pln ’ (that’s “asterisk”.pln) into the “File name” box and press enter. .pln files will be visible.
Provide Screenshot(s)/video(s) of the issue encountered:

Detail steps to reproduce the issue encountered:
With sim running, Options menu - click ‘Load/Save’. Click ‘Load’ in next window. That opens the selection window - no .pln files and no "Plan files (
.PLN)" option in the drop-down box. In “File name” box, type " *.pln " and the .pln files are visible.
PC specs for those who want to assist (if not entered in your profile)
Build Version # when you first started experiencing this issue:
possibly always
Are you on the Steam or Microsoft Store version?
Did you submit this to Zendesk? If so, what is your ticket #?