If you are using TeamViewer to remotely control other computers, a recent software change (not sure if it’s TeamViewer, display driver or Windows 10 itself) caused the text to be blurry because of scaling. There is no parameter in TeamViewer that can control the window size, it is set by TeamViewer depending on the display resolution on the guest system.
A work around is manually extending the size of the window; the text will be crisp again once the height is dragged to increase by just a few pixels. A better temporary solution is making use of a small utility program called AutoSizer since it can set an active window to any size and/or position on the screen. One click to scan all the active programs will automatically change TeamViewer to a preset window size that won’t cause the display to be scaled.