Understanding the Problem with Adding a Legend to a ggplot2 Plot

Extracting Coefficient Value from Legend in R Plots

Removing Black Lines from Fill Scale Legend using `geom_vline` and `geom_histogram` in R with ggplot2

Best Practices for Handling Missing Values in ggplot2: A Guide to Effective Visualization

Creating Custom Legends in ggplot2: A Comprehensive Guide

Customizing Raster Plot Legend Labels to Display Specified Breaks Value in R