Rendering glitches in overview mode

[thinkh]

• Release number or git hash: Caleydo@8fb3c96 equal to current develop branch at be45acf with lineupjs@^4.0.0-alpha.2
• Web browser version and OS: Chrome 69-beta

Steps to reproduce

1. Open https://taggle.caleydoapp.org/#soccer
2. Switch to overview mode
3. Scroll the ranking up and down

Observed behavior

• White spots at the header and footer, which makes the header invisible and unusable

Expected behavior

• Rendering without glitches

[thinkh]

Further testing shows, that these glitches only occur with certain viewport sizes (1920x1089 for the gif above) and the taggle_user_study branch.

The stable demo and develop demo do not show this behavior.

It would be good if someone else can test the taggle demo and see if the problem occurs as well.

[katush]

I tested the taggle demo and at my native resolution 1920x974 I don't have any of these problems, but when emulating different resolutions in chrome I run into similar issues in overview mode:

• on higher resolutions the demo was very laggy and some parts of the table didn't render at all
  
• if the windows size is smaller and some columns are accessible only by horizontal scrolling, they will sometimes not render (this happens if you switch to overview mode before horizontally scrolling to access them)
  

[katush]

And just a tiny cosmetic issue - the top pixels of the group name text remain visible in the overview mode.

[mstreit]

still valid?

[thinkh]

I tested it again and cannot confirm this behavior with LineUp v4.0.0-alpha.7 and Chrome 71-beta.

[mstreit]

I observed this again with the recent version:
https://lineup.js.org/app_develop/#soccer -> switch to overview

[mstreit]

@sgratzl, are you aware of the problem already?