On local development environments, everything seems fine. But those don't have any network latency.

On slower computers, slower browsers (think lots of extensions), or slower webservers (think xdebug enabled), this may also be visible.

As latency increases (as well as JS execution speed decreases), the problem becomes more pronounced. See the attached screencast, which demonstrates the absence of the problem at zero/very low latency, the presence of it at some latency, and the prominence at very high latency.

Proposed resolution


Remaining tasks

User interface changes

API changes

Data model changes

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Wim Leers created an issue. See original summary.

Wim Leers’s picture

Note: #2542050: Toolbar implementation creates super annoying re-rendering. solved exactly this sort of problem for Toolbar — but in doing so, it may actually have created this problem: because Toolbar now shows up instantaneously whereas it did not before, it's possible that it actually caused this.

Version: 8.4.x-dev » 8.5.x-dev

Drupal 8.4.0-alpha1 will be released the week of July 31, 2017, which means new developments and disruptive changes should now be targeted against the 8.5.x-dev branch. For more information see the Drupal 8 minor version schedule and the Allowed changes during the Drupal 8 release cycle.

droplet’s picture

Only pre-set HTML can solve this problem. (Or send new CSS to HEAD)

Probably, we need this issue first: #2696023: Save Users' Toolbar State config to serverside

and might be this also: #2391025: Add support for inline JS/CSS with #attached

a better deal would be this, get rid of this common errors from the design pattern, not code :) We have limitations on code side (e.g., caching vs non-caching is a headache already)
#2891332: Create a Toolbar 2 module

Or if you great enough, to slim down the scripts execution time to less than 16ms may work. I don't think we can. :P