InDesign duplicating paragraph styles

Unfortunately, I can confirm that this is a serious bug in InDesign beginning with version 18.x (2023) on the Windows platform. I haven't heard about it being a problem on Macs.

Regardless of how the import options are set when importing a styled Word document, Style Mapping isn't working correctly.

Examples:

• When mapping Normal (from MS Word) to My Body Text (in InDesign), Normal is still imported into the paragraph styles panel and applied to the text.
• When Heading 1 (from MS Word) is mapped to Heading 1 (in InDesign), the Styles panel will show two Heading 1 styles with the exact same name but different settings.
• Any Word style that is mapped to InDesign's [Basic Paragraph] with produce two [Basic Paragraph] styles in the panel. This is a real PITA because Adobe had fixed the ages-long problem with [Basic Paragraph] and it worked fine on the Windows platform for since around version 17. Now it's totally broken.
• Using the Map Styles function crashes InDesign about 90% of the time, especially when either [Basic Paragraph], [New Paragraph Style], or New Paragraph Style are selected.
• And the Style Mapping Presets crash InDesign, too. Mine is stuck on a Preset from a client's project, but when selecting either another Preset or setting it to None, InDesign crashes.

Other style problems happen when formatted text is copied from one INDD file into another. There's no warning pop-up or controls about how to handle incoming styles, so all of the incoming styles are duplicated at the bottom of the Paragraph Styles panel using the exact style name that's already in the destination file but having the settings of the incoming version.

It's a mess. What worked fairly seamlessly for decades has now become totally unusable on Windows. We've regressed backwards 20 years.