Just showing off the use of the {button} element to create a functional diacritics keyboard. Hope you find it useful!
{formparagraph: name=text; cols=50; rows=6}
{note: trim=left; insert=no; preview=yes; color=none}
{repeat: for c in split(other, "|")}{button: text={=concat(text,c)}; label={=c}}{endrepeat}
{repeat: for c in split(misc, "|")}{button: text={=concat(text,c)}; label={=c}}{endrepeat}
{formtoggle: name=Toggle CAPS; default=yes}{endformtoggle: trim=right}
{if: `Toggle CAPS`}
{repeat: for group in uc}{chars=split(group, "|")}
{repeat: for c in chars}{button: text={=concat(text,c)}
; label={=c}}{endrepeat}{endrepeat}
{else}
{repeat: for group in lc}{chars=split(group, "|")}
{repeat: for c in chars}{button: text={=concat(text,c)}; label={=c}}{endrepeat}{endrepeat}
{endif}
{other="ǂ|ʭ|ʔ|ʡ|ʖ|ǁ|ʕ|ǃ|ʢ"}
{misc="«|»|“|„|”|‘|‚|’|—|–|¿|¡|·|…|@|¼|½|¾|€"}
{uc=[
"A|Á|À|Â|Ǎ|Ä|Ā|Ă|Ã|Å|Ą|Ȧ|Ạ|Ǟ|Ǡ|Æ|Ǽ|Ǣ",
"B|Ḃ|Ḇ|Ḅ|Ɓ",
"C|Ç|Ć|Č|Ĉ|Ċ|Ƈ",
"D|Ð|Đ|Ɖ|Ď|Ḋ|Ḍ|Ḏ|Ḑ|Ɗ|Ꝺ|ẟ",
"E|É|È|Ê|Ě|Ë|Ē|Ĕ|Ẽ|Ę|Ȩ|Ė|Ẹ|Ẹ|Ə|Ǝ|Ɛ",
"F|Ḟ|FF|FI|FL|FFI|FFL|Ƒ",
"G|Ğ|Ĝ|Ġ|Ḡ|Ǵ|Ģ|Ǥ|Ǧ|G̃|Ɠ|Ȝ|Ᵹ|Ꝿ|Ɣ",
"H|Ḥ|Ḫ|H̱|Ĥ|Ȟ|Ħ|Ḣ|Ḩ|Ḧ|Ƕ",
"I|Í|Ì|Î|Ǐ|Ï|Ī|Ĭ|Ĩ|Į|İ|ı|Ị|Ɨ|IJ|Ɩ",
"J|Ĵ|J̌",
"K|Ķ|Ḳ|Ḵ|Ǩ|Ꝃ|Ƙ",
"L|Ł|Ĺ|Ľ|Ļ|Ŀ|Ḷ|Ḹ|Ꞁ",
"M|Ṃ|Ṁ",
"N|Ñ|Ń|Ň|Ǹ|N̄|Ņ|Ṅ|Ṉ|Ṋ|Ŋ|Ɲ|ɳ|Ꞑ",
"O|Ó|Ò|Ô|Ǒ|Ö|Ō|Ŏ|Õ|Ø|Ǿ|Ő|Ǫ|Ǭ|Ȯ|Ȱ|Ọ|Ȫ|Ȭ|Œ|Ɔ",
"P|P̄|Ṗ|Ƥ",
"Q|Ɋ",
"R|Ŕ|Ř|Ŗ|Ṟ|Ṛ|Ṝ|Ṙ|Ꞃ",
"S|Š|Ŝ|Ś|Ș|Ş|Ṣ|Ṡ|Ṥ|Ṧ|Ṩ|ẞ|S|ST|ST|Ꞅ",
"T|Ť|Ț|Ţ|Ṭ|Ṯ|Ŧ|Ṫ|T̈|Ƭ|Ʈ|Þ|Ꞇ",
"U|Ú|Ù|Û|Ǔ|Ü|Ū|Ŭ|Ů|Ű|Ũ|Ų|Ụ|Ǖ|Ǘ|Ǚ|Ǜ|Ʊ",
"V|V̇|Ʋ|Ʋ̇",
"W|Ŵ|Ẅ|Ẇ|Ƿ",
"X|Ẋ|Ẍ|Ꭓ",
"Y|Ý|Ŷ|Ÿ|Ȳ|Y̆|Ỹ|Ẏ|Ỵ|Ƴ",
"Z|Ž|Ź|Ż|Ẓ|Ẕ|Ȥ|Ƶ|Ʒ|Ǯ|Ƹ"
]}
{lc=[
"a|á|à|â|ǎ|ä|ā|ă|ã|å|ą|ȧ|ạ|ǟ|ǡ|æ|ǽ|ǣ",
"b|ḃ|ḇ|ḅ|ɓ",
"c|ç|ć|č|ĉ|ċ|ƈ",
"d|ð|đ|ɖ|ď|ḋ|ḍ|ḏ|ḑ|ɗ|ꝺ|ẟ",
"e|é|è|ê|ě|ë|ē|ĕ|ẽ|ę|ȩ|ė|ẹ|e̥|ə|ǝ|ɛ",
"f|ḟ|ff|fi|fl|ffi|ffl|ꝼ",
"g|ğ|ĝ|ġ|ḡ|ǵ|ģ|ǥ|ǧ|g̃|ɠ|ȝ|ᵹ|ꝿ|ɣ",
"h|ḥ|ḫ|ẖ|ĥ|ȟ|ħ|ḣ|ḩ|ḧ|ƕ",
"i|í|ì|î|ǐ|ï|ī|ĭ|ĩ|į|İ|ı|ị|ɨ|ij|ɩ",
"j|ĵ|ǰ",
"k|ķ|ḳ|ḵ|ǩ|ꝃ|ƙ",
"l|ł|ĺ|ľ|ļ|ŀ|ḷ|ḹ|ꞁ",
"m|ṃ|ṁ",
"n|ñ|ń|ň|ǹ|n̄|ņ|ṅ|ṉ|ṋ|ŋ|ɲ|ɳ|ꞑ",
"o|ó|ò|ô|ǒ|ö|ō|ŏ|õ|ø|ǿ|ő|ǫ|ǭ|ȯ|ȱ|ọ|ȫ|ȭ|œ|ɔ",
"p|p̄|ṗ|ƥ",
"q|ɋ",
"r|ŕ|ř|ŗ|ṟ|ṛ|ṝ|ṙ|ꞃ",
"s|š|ŝ|ś|ș|ş|ṣ|ṡ|ṥ|ṧ|ṩ|ß|ſ|ſt|st|ꞅ",
"t|ť|ț|ţ|ṭ|ṯ|ŧ|ṫ|ẗ|ƭ|ʈ|þ|ꞇ",
"u|ú|ù|û|ǔ|ü|ū|ŭ|ů|ű|ũ|ų|ụ|ǖ|ǘ|ǚ|ǜ|ʊ",
"v|v̇|ʋ|ʋ̇",
"w|ŵ|ẅ|ẇ|ƿ",
"x|ẋ|ẍ|ꭓ",
"y|ý|ŷ|ÿ|ȳ|y̆|ỹ|ẏ|ỵ|ƴ",
"z|ž|ź|ż|ẓ|ẕ|ȥ|ƶ|ʒ|ǯ|ƹ"
]}
{endnote: trim=no}