I have a dark mode in my Windows 10 [one of the very few things that in my experience improved from Windows 7]. It helps but it is not enough. And I cannot switch to high contrast. I experimented also with dark / high-contrast settings of mi graphics card, but these workarounds also proved to be inconvenient for the overall usage
As for the other workarounds and a big picture of this problem:
Here are some new facts in regards to my request: 1] Apparently Windows 7 does not have a Night Mode, to which option @stevehero has kindly pointed me towards. But it does have a Magnifier feature which holds the "invert colors" option. Unfortunately Mp3tag seen in negative is [at least for me] less readable [because of weak grid lines]; but it sure shows up a premise of a better looks when it will be somehow darkened. And on top of that: any other dark adjustment that I have already made, in…
In short: I have darkened [almost] everything I could in terms of operating system and software that I use [to few things I did not have time yet to get to]. I value these improvements and still view Mp3tag as being the single most bright drawback in my day-to-day opertions