If the game takes place, that means the NFL will have at least one game played on all seven days of the week over the course of the season, which has never happened in the modern era. During a normal year, you'll almost never see a Tuesday, Wednesday or Friday game get played, but this isn't a normal year and all three of those things are expected to happen.
Actually, the Tuesday game has already happened and that came back in Week 5 when the Titans beat the Bills 42-16. That game was originally supposed to be played on a Sunday, but it got moved to Tuesday after the Titans were hit by a COVID-19 outbreak. The game between Buffalo and Tennessee marked just the second time in 70 years that a game was played on a Tuesday. We're also scheduled to see another Tuesday game in Week 13 when the Ravens host the Cowboys.
As for Wednesday games, they're just as rare. Since 1950, the only time the NFL has played a Wednesday game came during the 2012 regular season opener. The Giants and Cowboys were originally scheduled to play on Thursday, but the game got bumped to Wednesday so that it didn't conflict with President Obama's speech at the Democratic National Convention that year.
When it comes to Friday games, those are actually slightly more common than you might think. Not only have there been three of them played since 2000, but there's actually one on the schedule this year and it has nothing to do with the pandemic. The Vikings and Saints are scheduled to play in the NFL's only Christmas game this year and if you look at the calendar, you'll notice that Dec. 25 is on a Friday in 2020.
As long as Vikings-Saints and Ravens-Steelers both get played, then the NFL will see its first season ever in the modern era with at least one game on each day of the week.