SumatraPDF has many advanced settings to customize look and behavior.
To open advanced settings file:
This opens a text file in Notepad with all the advanced settings. Make changes and save the file.
To reset to default settings, delete settings file and SumatraPDF will re-create it with default state.
Most settings take effect immediately after you save the settings file. Some settings (e.g. UseTabs) require closing and re-starting SumatraPDF.
Documentation for all settings is at
Here are some things you can customize:
Advanced settings file also stores the history and state of opened files so that we can e.g. re-open on the page