getting this error : incompatible encodings: UTF-8 and ASCII-8BIT

[shashankposhmark]

Using : Jruby-9.2.8.0 , Tilt:2.6.1 , slim (5.2.1),temple (0.10.3)
full error:

2026-03-15 22:56:25,279 [pool-7-thread-8] [69b79b883bc447f55bfb8914] ERROR jruby.queue_worker- Error: consume_send_email 
incompatible encodings: UTF-8 and ASCII-8BIT org/jruby/RubyString.java:2684:in `<<' 
/goshposh/server/lib/platform/email/../email_templates/liker_conversion/competing_offer.slim:28:in `__tilt_7939208' 
org/jruby/RubyMethod.java:120:in `call' /goshposh/jruby-9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:408:in 
`evaluate_method' /goshposh/jruby-9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:266:in `evaluate' /goshposh/jruby-
9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:134:in `render' 
/goshposh/server/lib/platform/email/../email_templates/liker_conversion/liker_conversion_layout.slim:100:in `__tilt_7939208' 
org/jruby/RubyMethod.java:120:in `call' /goshposh/jruby-9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:408:in 
`evaluate_method' /goshposh/jruby-9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:266:in `evaluate' /goshposh/jruby-
9.2.8.0/lib/ruby/gems/shared/gems/tilt-2.6.1/lib/tilt/template.rb:134:in `render' 
/goshposh/server/lib/platform/email/email_config_helper.rb:61:in `get_email' 

competing_offer.slim:

tr style="display:none;"
  td
    p style="display:none;font-size:1px;color:#333333;line-height:1px;max-height:0px;max-width:0px;opacity:0;overflow:hidden;"
      | Make your offer or buy now before it sells!
table.header.device-width.section align="center" style="background:#ffffff; border:none;border-top: 10px solid #602d35; border-bottom:1px solid #e6e2df;width:620px;margin:0 auto;font-size:12px;font-family:Helvetica,Arial,sans-serif;"
  tr
    td style="padding: 24px 16px 24px 16px;"
      table align="left" cellpadding="0" cellspacing="0" border="0" style="width:35%;height:45px;"
        tr
          td
            img.logo alt="Poshmark" src=="http://#{GoshPosh::Settings.asset_host}/assets/logo-horizontal@2x.png" style="display:block;border:0;width:100%;vertical-align:middle;"
      table align="right" cellpadding="0" cellspacing="0" border="0" style="color:#822432;width:60%;height:45px;text-align:center;"
        tr
          td style="font-size: 16px;vertical-align:middle;"
            | A new offer was just made on a listing you liked.
table.content.device-width.section align="center" border="0" cellspacing="0" cellpadding="0" style="background:#ffffff;width:620px;margin:0 auto; font-size:14px;font-family:Helvetica,Arial,sans-serif;"
  tr
    td style="padding:28px 30px 52px 30px;"
      table.main-content align="left" cellpadding="0" cellspacing="0" border="0" style="width:45%;height:200px"
        tr
          td align="center"
            a href=="#{construct_redirect_url("/listing/#{post_id}", :email, fvv_id, locals)}" title="#{post_title}" style="display:inline-block; vertical-align:middle; font-size:0;border:0;"
              img.listing-picture src=="#{post_cover_shot[:url]}" width="100%" alt="#{post_title}" style="display:block;border:0;"
      table.main-content align="right" cellpadding="0" cellspacing="0" border="0" style="color:#ffffff;width:50%;height:200px;"
        tr
          td style="text-align:center;vertical-align:middle;"
            p.main-content.text style="text-align:left; margin:0; padding:15px 0; color:#2a2a2a; font-size:20px; font-family:Helvetica,Arial,sans-serif; "
              strong "#{post_title}" 
              | is sure to sell soon—make an offer or buy now.
            p align="center" style="margin:0; padding:15px 0 0;"
              a href=="#{construct_redirect_url("/listing/#{post_id}", :email, fvv_id, locals)}" title="#{post_title}" style="-webkit-border-radius: 3px;-moz-border-radius: 3px;border-radius: 3px; color:#fff; background-color:#427fed;padding:9px 18px 9px; text-decoration: none; display:inline-block; font-size:14px; font-family:Helvetica,Arial,sans-serif; "
                | SHOP NOW

def get_template(template, force_reload = false)
          @thread_lock.synchronize do
            if @templates[template.to_sym].nil? || force_reload == true
              @templates[template.to_sym] = Tilt.new(@template_root+template, default_encoding: 'UTF-8')
            end
          end
          @templates[template.to_sym]
        end

def get_email(data)
         layout = get_template(config.template.layout, force_reload)
          body = get_template(config.template.body, force_reload)
          layout.render(scope, body: body, data: data)
end

data is all 'UTF-8' (#{post_title})
host encoding setup:
goshposh@ten-qw:/goshposh/server$ jruby -e 'p [Encoding.default_external, ENV["LC_ALL"], ENV["LC_CTYPE"], ENV["LANG"]]' [#<Encoding:UTF-8>, "en_US.UTF-8", nil, "en_US.UTF-8"]

Getting this error after upgrading slim (1.2.2) to slim (5.2.1),temple (0.4.0) to temple (0.10.3),tilt (1.3.7) to tilt (2.6.1)