Background:
Created a custom views block to use unformatted view showing fields set under 'Format'.
Also, created an override template as views-view-fields--bookstheme--block.html.twig and then created the HTML structure within this custom template and then I am simply printing the field like for example Eg:- {{ fields.booktitle.content}}
Below is attempt within to get the image field URL.
Observation:
Solution Attempt #1 worked for me and Solution Attempt #2 didnt. Request help on what I missed out.
Solution Attempt #1: [ Works ]
{# Below image field from view o/p #}
{{ fields.field_books_theme_pic.content }}
{# Creating a Field URI post setting up relationship to image field fields.uri.content gives uri format eg:- public://image.jpg #}
{{ fields.uri.content|striptags|trim }}
{# and this gives the image uri for src ref #}
{{ file_url(fields.uri.content|striptags|trim) }}
Solution Attempt #2 [ Something missing, no output ]
{% set url = fields.field_books_theme_pic.content|render|striptags %}
{{ url }}