public static MarkupRange ApplyInlineTag(MshtmlMarkupServices markupServices, _ELEMENT_TAG_ID tagId, string attributes, MarkupRange selection, bool toggle)
        {
            HtmlStyleHelper htmlStyleHelper = new HtmlStyleHelper(markupServices);

            // Aligning the with the behavior of Word, we will make <SUP> and <SUB> mutually exclusive.
            // That is, if you are applying <SUB> to a selection that has <SUP> applied already, we will first remove the <SUP>, and vice versa.
            // Wait, if empty and we're on the very end of the already existing formatting, then we just want to jump out and apply...

            MarkupRange selectionToApply = selection.Clone();

            if (toggle)
            {
                // If already entirely inside the tag
                //     If empty and just inside of the closing tag, then jump outside the closing tag
                //     Else remove the tag
                // If already entirely outside the tag
                //     If empty, apply the tag and put selection inside
                //     If non-empty, then apply tag and reselect
                // If partially inside the tag
                //     Remove the tag

                _ELEMENT_TAG_ID mutuallyExclusiveTagId = _ELEMENT_TAG_ID.TAGID_NULL;
                switch (tagId)
                {
                case _ELEMENT_TAG_ID.TAGID_SUP:
                    mutuallyExclusiveTagId = _ELEMENT_TAG_ID.TAGID_SUB;
                    break;

                case _ELEMENT_TAG_ID.TAGID_SUB:
                    mutuallyExclusiveTagId = _ELEMENT_TAG_ID.TAGID_SUP;
                    break;

                default:

                    break;
                }

                if (selection.IsEmpty())
                {
                    // If the selection is empty and we're just inside the tagId closing tag (meaning that there is no text before the closing tag),
                    // then we just hop outside of the tagId closing tag.

                    bool          exitScopeMatchesTagIdToBeApplied;
                    MarkupPointer pointerOutsideTagIdScope = htmlStyleHelper.NextExitScopeWithoutInterveningText(selection,
                                                                                                                 tagId,
                                                                                                                 mutuallyExclusiveTagId,
                                                                                                                 out exitScopeMatchesTagIdToBeApplied);

                    if (pointerOutsideTagIdScope != null)
                    {
                        selectionToApply = markupServices.CreateMarkupRange(pointerOutsideTagIdScope, pointerOutsideTagIdScope);
                        if (exitScopeMatchesTagIdToBeApplied)
                        {
                            return(selectionToApply);
                        }
                        // else we still need to apply tagId
                    }
                }

                // If a mutually exclusive tag is applied, then remove it.
                if (selectionToApply.IsTagId(mutuallyExclusiveTagId, true))
                {
                    selectionToApply.RemoveElementsByTagId(mutuallyExclusiveTagId, false);
                }

                // If this tag is already applied, then remove it and return.
                if (selectionToApply.IsTagId(tagId, true))
                {
                    selectionToApply.RemoveElementsByTagId(tagId, false);
                    return(selectionToApply);
                }
            }

            return(htmlStyleHelper.ApplyInlineTag(tagId, attributes, selectionToApply));
        }