metacodes

The root cause is that `hStackView.fittingSize.width` sometimes is different. For those smaller icons, `hStackView.fittingSize.width` is smaller than others. I try to play sliders `windowMaxWidthInRow`, `windowMinWidthInRow` and `iconSize`, it can solve...

> if you're interested in this, could you draft some mock designs? Like pen and paper or even ascii art where you would sketch how the new UI would look...

@lwouis This is the current design for the `Thumbnail focused` theme. I referenced the design of HyperSwith's configuration options. I'm not a professional UI designer, I just learned Sketch, there...

@lwouis I use new method to aovid subcribing to applications without windows. See details in the code comments. Currently testing is OK. Need more testing.

@lwouis I have submitted a new commit for fixing #1324 and some minor improvements to full-screen thumbnails.

> @metacodes I'll close this PR now since I merged part of it. If you're still interested in improving perf, could you please open a new PR with your new...

有些是因为服务器端接口没有返回历史数据，最近几天是这样子的。所以比较希望能够提供历史数据本地保存的功能，这样如果用这个客户端，就可以加载本地的历史记录，不用怕服务器没有历史记录返回。 @lencx 增加这个功能是否可行呢？最近一直在找能够这样保存历史对话的客户端。