Non-exclusive topic suggestions:
sex discrimination and mass media
mass shootings and reporting
mass media influence
(misinformation or disinformation or fake news)
media consumption
mass media and public opinion
effective advertising
mergers and media
mass media industry
online social networks
online journalism
stereotypes in mass media
journalism research
mass media and audience research
mass media and race relations
objectivity in journalism
mass media and politics
and many more…