No, no, yeah.There is no good practice established, use which pleases you better. There are no differences for the browser since the way you use does not break the HTML syntax and generate unexpected results (but there was your error, not the browser) and yes, you can use whatever you prefer.As https://www.w3.org/TR/html4/intro/sgmltut.html#h-3.2.2 , you can use double quotes, simple quotes and even quotation marks. It doesn't matter.By default, SGML requires that all attribute values be delimited using either double quotation marks (ASCII decimal 34) or single quotation marks (ASCII decimal 39)By default the SGML (Standard Generalized Markup Language) requires all attribute values to be delimited by double quotation marks (character 34 of the ASCII table) or simple quotes (character 39 of the ASCII table).In certain cases, authors may specify the value of an attribute without any quotation marks. The attribute value may only contain letters (a-z and A-Z), enters (0-9), hyphens (ASCII decimal 45), periods (ASCII decimal 46), underscores (ASCII decimal 95), and colons (ASCII decimal 58). We recommend using quotation marks even when it is possible to eliminate them.By translating, in certain cases authors can specify the value of an attribute with no aspa. In this case the value of the attribute can have only letters (a-zA-Z), digits (0-9), hyphens, points, underlines and two points. The same specification also recommends avoiding this practice whenever possible - without further reasons.So use whatever you prefer. It is probably always recommended to use or simple or double for one day if one of them is required you do not need to correct your code..text-red {
color: red;
}<div class="text-red">Com aspas duplas</div>
<div class='text-red'>Com aspas simples</div>
<div class=text-red>Sem aspas</div>It is also noted that the use of both precisely to allow to use the characters in their values, as well as with other languages. If you define the value with double quotes, the simple aspa will not break the syntax; the reciprocal is true.But in all cases you can represent the character with your code without interfering with the HTML syntax. For example, to use double quotes in a value defined by double quotes you can do:<a title="Valor do "title" com aspas duplas">Veja o title</a>O title of the anchor will Valor do "title" com aspas duplas even if it was defined with double quotes.But why did the editor complain about the simple quotes?It should be internal configuration of the editor in order to maintain consistency in the project. It is more common to use double quotes and probably the editor is configured to use double quotes. When used the simple quotes it will issue this Alert (not one error) that maybe you should reconsider your code. If in all the project is used the double quotes, why there use simple quotes? It is probably configurable and if you want to use the simple quotes, you can do so and the message will appear whenever you use double quotes.
