Selected start month is visible in next and previous years

[bogdankol]

Describe the bug
A clear and concise description of what the bug is.

You can see this on https://reactdatepicker.com/#example-date-range -> Exclude Months in Range Month Picker.
If you select a range of months the starting month is being seen in next and previous years thought it is not in picked date range

To Reproduce
Steps to reproduce the behavior:

1. Go to https://reactdatepicker.com/#example-date-range -> Exclude Months in Range Month Picker
2. Click on calendar range field
3. Set a range of month for example from Jan 2025 to Sep 2025 and press buttons to pick any next or previuos year
4. You should see that starting month is highlighted in wrong years

Expected behavior
A clear and concise description of what you expected to happen.

In years that are not in selected months range you shouldn't see any month highlighted

Screenshots
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Desktop (please complete the following information):

• OS: Win11
• Browser chrome
• Version 136.0.7103

Additional context
Add any other context about the problem here.

[SaiBalaji202]

Hi,
I think it is working as expected only. For example I selected July to Sept in 2024.

When I switch to 2025, I didn't notice the same highlight applied here.

If you are thinking why July month is highlighted here, it's actually not selected, but pre-selected for keyboard navigation to start from the previously selected date range. If you notice the highlight color is different for the selected date range and this pre-selected month

[martijnrusschen]

Thanks for reporting this! After investigating, this behavior is actually working as intended.

The highlighting you're seeing is the keyboard preselection indicator, not a bug. When you navigate between years, the datepicker maintains a preSelection date for keyboard accessibility - this allows users navigating with arrow keys to see which month will receive focus.

Looking at the code:

• isSelectedMonth() correctly checks both month AND year before applying the --selected class
• The --keyboard-selected class only appears when preSelection is in the same year as the displayed calendar

I added some tests to verify this behavior:

• Keyboard-selected class does NOT appear when preSelection is in a different year
• Range highlighting correctly respects year boundaries

That said, I understand the visual feedback can be confusing. If you'd like to see different styling for keyboard preselection vs actual selection, that would be a valid feature request/UX improvement rather than a bug fix.

Closing this as working as intended, but happy to discuss further if you have questions!