无法在R Shiny应用中集成Leaflet-labeler插件的技术求助

我需要在R Shiny的Leaflet地图中实现leaflet-labeler插件，目前进展不顺。我的GeoJSON数据是点图层FeatureCollection，每个要素包含用于显示为标签的HTML格式label属性（通过jsonlite::fromJSON读取），目标是实现插件的标签碰撞避免功能，达到类似GitHub示例的效果。

数据（dput(geojson)输出） #

list(type = "FeatureCollection", features = list(list(type = "Feature", 
    properties = list(punto = 1L, unicode = "štéĭnle̤", 
        html = "štéĭnle̤", label = "<em style=\"color:#ec008d\">1</em> štéĭnle̤"), 
    geometry = list(type = "Point", coordinates = list(8.423711786, 
        46.38731673))), list(type = "Feature", properties = list(
    punto = 229L, unicode = "s̓as̓ét", html = "s̓as̓ét", 
    label = "<em style=\"color:#ec008d\">229</em> s̓as̓ét"), 
    geometry = list(type = "Point", coordinates = list(11.00240679, 
        46.1641373))), list(type = "Feature", properties = list(
    punto = NULL, unicode = NULL, html = NULL, label = "<em style=\"color:#ec008d\">NA</em> "), 
    geometry = list(type = "Point", coordinates = list(13.30003463, 
        42.79799721))), list(type = "Feature", properties = list(
    punto = NULL, unicode = NULL, html = NULL, label = "<em style=\"color:#ec008d\">NA</em> "), 
    geometry = list(type = "Point", coordinates = list(13.3426341, 
        41.6396009))), list(type = "Feature", properties = list(
    punto = 941L, unicode = "na pet̬ři̍d̰d̰a", html = "na pet̬ři̍d̰d̰a", 
    label = "<em style=\"color:#ec008d\">941</em> na pet̬ři̍d̰d̰a"), 
    geometry = list(type = "Point", coordinates = list(16.31308204, 
        39.31875679))), list(type = "Feature", properties = list(
    punto = 214L, unicode = "s̓as̓ẹdẹli̍n", html = "s̓as̓ẹdẹli̍n", 
    label = "<em style=\"color:#ec008d\">214</em> s̓as̓ẹdẹli̍n"), 
    geometry = list(type = "Point", coordinates = list(10.88553927, 
        46.33220307))), list(type = "Feature", properties = list(
    punto = 828L, unicode = "u vrəččə͐tíe͐ddə", html = "u vrəčč<sup>ə</sup>tí<sup>e</sup>ddə", 
    label = "<em style=\"color:#ec008d\">828</em> u vrəčč<sup>ə</sup>tí<sup>e</sup>ddə"), 
    geometry = list(type = "Point", coordinates = list(16.4131601, 
        41.1534886))), list(type = "Feature", properties = list(
    punto = 764L, unicode = "perdiǧèd̰ḏ͐a", html = "perdiǧèd̰<sup>d̰</sup>a", 
    label = "<em style=\"color:#ec008d\">764</em> perdiǧèd̰<sup>d̰</sup>a"), 
    geometry = list(type = "Point", coordinates = list(9.655999729, 
        39.92658912))), list(type = "Feature", properties = list(
    punto = NULL, unicode = NULL, html = NULL, label = "<em style=\"color:#ec008d\">NA</em> "), 
    geometry = list(type = "Point", coordinates = list(14.1635845, 
        42.347886))), list(type = "Feature", properties = list(
    punto = 806L, unicode = "pətrəččòla , vrəččo̍dda", 
    html = "pətrəččòla , vrəččo̍dda", 
    label = "<em style=\"color:#ec008d\">806</em> pətrəččòla , vrəččo̍dda"), 
    geometry = list(type = "Point", coordinates = list(15.63804725, 
        41.71244172)))))

尝试的实现代码 #

UI部分 #

library(shiny)
library(leaflet)
library(leaflet.extras)
library(htmltools)
library(htmlwidgets)

ui <- fluidPage(
    tags$head(
             tags$script(src = "leaflet-labeler.js"),
             tags$link(src = "leaflet-labeler.css")
             ),
    leafletOutput("map")
  )

SERVER部分 #

server <- function(input, output, session) {
labeler <- htmlDependency(
  name = "leaflet-labeler",
  version = "1.0.0",
  src = c(file = normalizePath("app\\www")),
  script = "leaflet-labeler.js",
  stylesheet = "leaflet-labeler.css"
)

registerPlugin <- function(map, plugin) {
  map$dependencies <- c(map$dependencies, list(plugin))
  map
}

leaflet() %>% 
  addTiles()%>%
  #addGeoJSON(geojson_data) %>% works up to here
  registerPlugin(labeler) %>%
  onRender(
    "
    function(el, x, geojson) {

    const layer = L.labeler(geojson, {
    labelProp: 'label', 
    labelPos: 'auto'
    }).addTo(this);
    ",
    data = geojson)
}

问题现状 #

目前地图上没有渲染任何标签内容；但添加GeoJSON图层时标记能正常显示，说明数据本身无问题。由于完全不熟悉JavaScript，无法排查插件应用中的细节问题，恳请提供技术建议。

内容的提问来源于stack exchange，提问作者eazyezy