“Stylesheet” is M$ Office vocabulary. In LO Writer, you have no such “sheet”. You play with styles, of course paragraph styles which are universally known, but also character, page, frame and list. I put aside so-called table styles which are in fact templates and don’t behave as other “regular” styles.
Custom styles are kept in a template document, which is an ordinary document “blessed” by a specific extension .ott conferring it special properties, among which the equivalent (and more) of stylesheets. When you open a template, you inherit all the styles stored into it, plus the optional default content or outline you have put inside.
The answer to your question is: do not use toolbar buttons but design paragraph AND character styles to meet your needs. Remember that toolbar button are quick’n’dirty shortcuts which will set somewhat artificially some attributes in an anonymous style. Bold and italic buttons are perfect examples of this.
I have no Cormorant but Baskerville in my collection comes in 6 faces. I select a specific face in the Font
tab of style dialogs in the Style box to set a weight and an angle for this style.
Afterwards, I only use my custom styles (paragraph or character depending on context).
The only disadvantage is that currently applying several character styles to a run of text is an experimental feature. Consequently, you must design several combinations of attributes in case you play not only with weight and angle but also with other Font Effects
.
EDIT 2019-2-18
I design my styles within Writer, leaving to it the burden of translating the UI options into ODF. This way, I don’t struggle with the spec and its version changes.
My idea with multi-face fonts is to select the weight/angle variant as if it was a “regular” face and use it without applying stylistic variation.
I had a look at the result for Baskerville SemiBold Italic:
<office:font-face-decls>
<style:font-face style:name="Baskerville" svg:font-family="Baskerville" style:font-adornments="SemiBold Italic" style:font-pitch="variable"/>
</office:font-face-decls>
This section is empty in your .fodt; maybe, this makes a difference.
and
<style:style style:name="Text_20_body" style:display-name="Text body" style:family="paragraph" style:parent-style-name="Standard" style:class="text">
<style:paragraph-properties fo:margin-top="0cm" fo:margin-bottom="0.212cm" style:contextual-spacing="false"/>
<style:text-properties style:font-name="Baskerville" fo:font-family="Baskerville" style:font-style-name="SemiBold Italic" style:font-pitch="variable" fo:font-style="italic" fo:font-weight="600" style:font-size-asian="10.5pt" style:font-weight-asian="normal"/>
</style:style>
I suggest you tune your existing styles from within Writer, selecting another face then reselecting the original one to see if it creates a different set of XML attributes.
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