Plotly.py 4.5, Plotly Express no longer puts the = in trace names, because legends support titles (source).
Prior to Plotly.py 4.5, I had used this ‘hover_data’ trick to remove the ‘=’ from the legend trace names.
hover_data=['gain_loss']).for_each_trace(lambda t: t.update(name=t.name.split("=")[0])
However now with Plotly.py 4.5, I want to remove the legend title. The new trick to do that is to enter empty string in the new legend title in the fig.update.layout section.
fig.update_layout({ 'legend_title_text': ''
This is much cleaner look for legends where the trace names, and your chart title, are sufficiently explanatory and a legend title would be superfluous.