As workaround for those with just one monitor (or many but the same size), I tried what Kristo Ojasaar (kristoo) already suggested and I found something even simpler. There is no needs for the 'Tweak'-tool: For a 4k monitor, set it to 100% and go to Settings -> Universal Access and activate 'large text'. Now the 'scaling' is more or less what 125% under Ubuntu 19.10 used to be.
Seeing something so simple solving this, I wonder why the developers do not a define a css style-sheet (or however the gui colors / font size etc are defined) for the different scaling options and apply these as soon e.g. '125%' scaling is activated.
As workaround for those with just one monitor (or many but the same size), I tried what Kristo Ojasaar (kristoo) already suggested and I found something even simpler. There is no needs for the 'Tweak'-tool: For a 4k monitor, set it to 100% and go to Settings -> Universal Access and activate 'large text'. Now the 'scaling' is more or less what 125% under Ubuntu 19.10 used to be.
Seeing something so simple solving this, I wonder why the developers do not a define a css style-sheet (or however the gui colors / font size etc are defined) for the different scaling options and apply these as soon e.g. '125%' scaling is activated.