Theme development

When I went to clear my cache on my Drupal 8.5.3 site using Drush, I got the above-referenced error message. I was able to clear the cache through the menu system, but this slows me down.

After doing some research, it appears that this is a symphony problem with a simple solution of changing the yaml files to UTF-8. So, I went into Notepad++ and opened my *.info.yml and *.libraries.yml to see if they were encoded in a different format. Nope, they were both UTF-8.

Has anyone else encountered this error and/or can someone lead me in the right direction?

Steve

Using a block twig template file, I'm trying to output the value of a block field called "field_link". If I add  {{ kint(content) }}, clear cache and reload the page, I then see an enormous array and see  an element called ['_field_layout'], then one called ['first’], then under that, a "field_link". That sounds promising, but I don't see url data yet, so I tried then to output  {{ kint(content['_field_layout']) }} to see if I could get more specific and detailed data. I cleared cache, then returned to the page, and it forces a load of the drupal installation page.

Hello , gyus, hope you can help me.

How redeclare fumction rdf module?

I want rewrite funciton module module rdf

http://prntscr.com/jarn2z

http://prntscr.com/jarngu

I type in template.php 

http://prntscr.com/jarnvh

But it's not redacle or mistake sometimes.

HOw can i type my url, redacle this function rdf module in teamplate.php?

I need a different form field rendering depending on the form attributes.

In general, does anybody know a way of getting the parent of the current element in preprocess and suggestions theme hooks?

Just a curiosity, I've got a D8 sub theme that I'd like to control some specific content for. Part of that content is 3 links on the main menu that are only relevant if this theme is used. I thought maybe the theme install worked similar to the module install and process a .links.menu.yml file if one existed in the theme. 

Anyway, curious if this is supported or not and if it is, what I may be doing wrong. Thanks

I'm trying to rebuild the Bootstrap 3.3.7 menu to Bootstrap 4.1
In links it is necessary to receive a class active instead of is-active

{% import _self as menus %}

{{ menus.menu_links(items, attributes, 0) }}

{% macro menu_links(items, attributes, menu_level) %}
{% if items %}
{% if menu_level == 0 %}
<ul class="navbar-nav mr-auto">

{% for item in items %}