Color change bug for PrusaSlicer / BambuStudio

bug.txt

Alternate order of colors between slices to reduce color changes (faster prints w/ less waste).

If I'm not mistaken, the slicer currently has a very naive color changing strategy, which leads to massive waste of filament:
⚫️¹🔄⚪️¹🔄
⚫️²🔄⚪️²🔄
⚫️³🔄⚪️³🔄
⚫️⁴🔄⚪️⁴🔄
...

(layer numbers are in superscript, 🔄 indicates a color change + expensive purge, including a go on the purge tower)

It seems that one could cut the number of color changes by keeping the last color of a slice to start the next slice (with a brief pause to ensure the previous layer has cooled, similar to what is already done for single color printing):
⚫️¹🔄⚪️¹⏸
⚪️²🔄⚫️²⏸
⚫️³🔄⚪️³⏸
⚪️⁴🔄⚫️⁴⏸
...


Assuming the pause between layers is negligible, with two colors, this would save half of the color changes.
In general this saves 1/N of color changes for N-color prints.
🔴¹🔄🟢¹🔄🔵¹🔄
🔴²🔄🟢²🔄🔵²🔄
🔴³🔄🟢³🔄🔵³🔄
🔴⁴🔄🟢⁴🔄🔵⁴🔄
...

Keep last color of a slice to start next slice (after short pause):
🔴¹🔄🟢¹🔄🔵¹⏸
🔵²🔄🔴²🔄🟢²⏸
🟢³🔄🔴³🔄🔵³⏸
🔵⁴🔄🔴⁴🔄🟢⁴⏸
...

While this could in theory be implemented by some G-code post processor, it seems a bit challenging to do so (esp. when purge towers are involved).

Any thoughts?