SumatraPDF has many advanced settings to customize look and behavior.

To open advanced settings file:

This opens a settings text file in default .txt editor. Make changes and save the file.

To reset to default settings, delete settings file. SumatraPDF will re-create it with default values.

Most settings take effect immediately after saving the settings file. Some settings (e.g. UseTabs) require closing and re-starting SumatraPDF.

Documentation for all settings is at https://www.sumatrapdfreader.org/settings/settings

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